Pyrrolo[1,2-a]pyrimidine compound and heat-sensitive recording material using the same

An object of the present invention is to provide a pyrrolo[1,2-a]pyrimidine compound that is useful as a coupler providing excellent hue of a cyan system and sufficient density of formed color. The pyrrolo[1,2-a]pyrimidine compound of the present invention for achieving the object is represented by one of following general formulae (1), (2) and (3). ##STR1##

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 The present invention relates to a pyrrolo[1,2-a]pyrimidine compound that
 is useful as a coupler of a photographic material, a heat-sensitive
 recording material and the like, and to a heat-sensitive recording
 material that contains as color forming components the
 pyrrolo[1,2-a]pyrimidine compound serving as a coupler and a diazonium
 salt compound.
 2. Description of the Related Art
 With the recent advancement in performance of heat-sensitive recording
 materials, it has been strongly required to develop a heat-sensitive
 recording material that has cyan-color forming property and shows
 excellent hue, density of the formed color, and the like, in which shelf
 life, storability of images, image fixing property and the like are
 improved.
 Diazonium salt compounds are compounds that have very high chemical
 activity and react with compounds called couplers (e.g., phenol
 derivatives, compounds having an active methylene group) to form an azo
 dye easily. Diazonium salt compounds are also light-sensitive and lose
 their activity when decomposed due to irradiation of light. Therefore,
 diazonium salt compounds have been used as light recording materials such
 as those used for diazo copies (see, "Shashin Kogaku no Kiso, Higin-en
 Shashin Hen (Fundamentals of Photographic Engineering, Edition of
 Non-Silver Salt Photography)" edited by Nippon Shashin Gakkai (Japan
 Photographic Association), Corona Co., Ltd. (1982), pp. 89 through 117,
 and pp. 182 through 201).
 Further, by utilizing the property of diazonium salt compounds that they
 lose their activity due to decomposition by light, diazonium salt
 compounds have recently been used in recording materials that require
 fixing of images. As a representative example, there has been proposed a
 heat-sensitive recording material of a light fixing type in which a
 diazonium salt compound and a coupler are heated in accordance with image
 signals and react to form images, and thereafter, the images are fixed by
 irradiation of light (Hirotsugu Sato et al., "Gazo Denshi Gakkai Shi
 (Journal of the Image Electronics Society)", Vol. 11, No. 4 (1982), pp.
 290-296, etc.).
 However, the above-described recording materials using as a color forming
 element a diazonium salt compound have a drawback in that the activity of
 the diazonium salt compound is extremely high, and even in dark places,
 the diazonium salt compound thermally decomposes gradually such that the
 reactivity thereof is lost, and therefore, its shelf life as a recording
 material is short.
 As one means for improving the above drawback, a method is known in which a
 diazonium salt compound is encapsulated in microcapsules. It has become
 possible by the above method to isolate the diazonium salt compound from
 substances promoting decomposition such as water, bases and the like, and
 to greatly improve the shelf life as a recording material (Tomomasa Usami
 et al., "Denshi Shashin Gakkai Shi (Journal of the Electrophotographic
 Association)", Vol. 26, No. 2, (1987), pp. 115 through 125). When the
 microcapsule is a microcapsule having a wall that has a glass transition
 temperature and in which the glass transition temperature is somewhat
 higher than room temperature such as urea resin and urethane resin, the
 capsule is called a heat-responsive microcapsule and is useful as a
 heat-sensitive recording material since, at room temperature, capsule
 walls exhibit non-permeability with respect to substances and, at the
 glass transition temperature or higher, exhibits permeability with respect
 to substances. In other words, if a heat-sensitive recording layer, which
 comprises heat-responsive microcapsules containing a diazonium salt
 compound, a coupler and a base, is applied onto a substrate to form a
 recording material, the diazonium salt compound can be kept stable for a
 long period of time, a color-formed image can be easily formed by heating,
 and further, the image can be fixed by irradiation of light.
 As described above, it has become possible to greatly improve the stability
 of a diazonium salt compound by encapsulating the compound in
 microcapsules.
 On the other hand, it is known that when 2-hydroxy-3-naphtoic anilides are
 used as couplers, they are excellent as color forming materials for
 heat-sensitive recording, and if a coupling reaction is effected with a
 4-substituted amino-2-alkoxybenzene diazonium salt compound, a blue dye
 can be formed (Japanese Patent Application Laid-Open (JP-A) No. 2-225082).
 However, the diazonium salt compound has a drawback in that, when a
 diazonium salt compound having .lambda..sub.max at a longer wavelength
 side is used, storability before use (background coloring property during
 storage before copying) of the recording material deteriorates. Further,
 in the case of a diazonium salt compound having .lambda..sub.max at a
 shorter wavelength side, when the aforementioned 2-hydroxy-3-naphtoic
 anilides are used, there are drawbacks in that the fixing property of
 images when irradiated with light is hindered, the hue extends over a long
 wavelength even to cyan, and further, storability of color-formed images
 (light fastness) is not sufficient.
 As described above, there has not been obtained until now a heat-sensitive
 recording material that not only has a cyan color forming property but
 also provides excellent hue and sufficient density of the formed color,
 which results in satisfactory shelf life, image storability and image
 fixing property.
 SUMMARY OF THE INVENTION
 An object of the present invention is to provide a pyrrolo[1,2-a]pyrimidine
 compound that is useful as a coupler providing excellent hue of a cyan
 system and sufficient density of formed color, and a novel heat-sensitive
 recording material of a cyan color forming type that contains the
 pyrrolo[1,2-a]pyrimidine compound serving as a coupler and a diazonium
 salt compound so as to have excellent shelf life, image light-resistance,
 image fixing property and the like in addition to excellent hue and
 density of the formed color.
 The present inventors have studied couplers intensively, and have found
 that novel pyrrolo[1,2-a]pyrimidine compounds represented by the following
 general formulae (1), (2) and (3) are useful as couplers that provide
 excellent hue of the cyan system and sufficient density of the formed
 color. Further, the inventors have found that a heat-sensitive recording
 material using the above pyrrolo[1,2-a]pyrimidine compound and a diazonium
 salt compound that will be described below has improved shelf life, image
 light-resistance and image fixing property, and has an excellent cyan
 color forming property. Thus, the inventors have accomplished the present
 invention.
 A pyrrolo[1,2-a]pyrimidine compound according to a first aspect of the
 present invention is represented by following general formula (1):
 ##STR2##
 wherein, in the general formula (1), R.sup.1 and R.sup.2 each independently
 represents a hydrogen atom, halogen atom, aryl group, alkyl group, cyano
 group, acyl group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl
 group, alkylsulfonyl group or arylsulfonyl group; and R.sup.3 represents
 an electron attractive group whose Hammett's substituent constant
 .sigma..sub.p value is equal to or larger than 0.20.
 A pyrrolo[1,2-a]pyrimidine compound according to a second aspect of the
 present invention is represented by following general formula (2):
 ##STR3##
 wherein, in the general formula (2), R.sup.1 and R.sup.2 each independently
 represents a hydrogen atom, halogen atom, aryl group, alkyl group, cyano
 group, acyl group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl
 group, alkylsulfonyl group or arylsulfonyl group; and X represents CO or
 SO.sub.2.
 A pyrrolo[1,2-a]pyrimidine compound according to a third aspect of the
 present invention is represented by following general formula (3):
 ##STR4##
 wherein, in the general formula (3), R.sup.19 and R.sup.20 each
 independently represents a hydrogen atom, halogen atom, aryl group, alkyl
 group, cyano group, acyl group, substituted carbamoyl group,
 alkoxycarbonyl group, aryloxycarbonyl group, acyloxy group, alkoxy group,
 aryloxy group, alkylthio group, arylthio group, substituted sulfamoyl
 group, alkylsulfonyl group, arylsulfonyl group, alkylphosphoryl group,
 arylphosphoryl group or substituted amino group; R.sup.30 and R.sup.40
 each independently represents a hydrogen atom, alkyl group, aryl group,
 cycloalkyl group, piperidyl group, acyl group, --C.sub.n H.sub.2n
 N(R.sup.50)(R.sup.60) or --C.sub.m H.sub.2m XC.sub.1 H.sub.21
 N(R.sup.70)(R.sup.80); R.sup.50 through R.sup.80 each independently
 represents a hydrogen atom, alkyl group or aryl group; X represents an
 oxygen atom, sulfur atom or N(R.sup.90)--; R.sup.90 represents a hydrogen
 atom, alkyl group or aryl group; R.sup.30 and R.sup.40, or R.sup.50 and
 R.sup.60, or R.sup.70 and R.sup.80, or R.sup.70 and R.sup.90, or R.sup.80
 and R.sup.90 may combine with each other to form a ring, and in the case
 of ring formation, they may contain a hetero atom; and n, m and 1
 represent integers from 1 through 12.
 A method of preparing a pyrrolo[1,2-a]pyrimidine compound of the present
 invention is a method of preparing the pyrrolo[1,2-a]pyrimidine compound
 of the third aspect of the present invention, wherein a
 pyrrolo[1,2-a]pyrimidine compound represented by following formula (A) is
 first reacted with chlorosulfonylisocyanate (ClSO.sub.2 NCO), and
 thereafter, reacted with HN(R.sup.30)(R.sup.40):
 ##STR5##
 wherein, R.sup.19 and R.sup.20 in the formula (A) have the same meanings as
 those of R.sup.19 and R.sup.20 in the general formula (3) of the third
 aspect, respectively; and R.sup.30 and R.sup.40 in HN(R.sup.30)(R.sup.40)
 have the same meanings as those of R.sup.30 and R40 in the general formula
 (3) of the third aspect, respectively.
 A heat-sensitive recording material of the present invention comprises a
 substrate, and on the substrate, a heat-sensitive recording layer contains
 a diazonium salt compound and a coupler that forms color by reacting with
 the diazonium salt compound during heating, wherein the coupler contains
 at least one type selected from the pyrrolo[1,2-a]pyrimidine compound
 represented by the general formula (1) of the first aspect, the
 pyrrolo[1,2-a]pyrimidine compound represented by the general formula (2)
 of the second aspect and the pyrrolo[1,2-a]pyrimidine compound represented
 by the general formula (3) of the third aspect of the present invention.
 In a heat-sensitive recording material of the present invention, maximum
 absorption wavelength .lambda..sub.max of the diazonium salt compound is
 preferably 450 nm or less, and the diazonium salt compound is preferably
 at least one type of the compounds represented by one of following general
 formulae (4) through (6):
 ##STR6##
 wherein, in the general formula (4), Ar represents a substituted or
 unsubstituted aryl group; R.sup.11 and R.sup.12 each independently
 represents a substituted or unsubstituted alkyl group, or a substituted or
 unsubstituted aryl group; R.sup.11 and R.sup.12 may be the same or
 different from each other; and X.sup.- represents an acid anion;
 ##STR7##
 wherein, in the general formula (5), R.sup.14, R.sup.15 and R.sup.16 each
 independently represents a substituted or unsubstituted alkyl group, or a
 substituted or unsubstituted aryl group; R.sup.14, R.sup.15 and R.sup.16
 may be the same or different from each other; Y represents a hydrogen atom
 or a --OR.sup.13 group; R.sup.13 represents a substituted or unsubstituted
 alkyl group, or a substituted or unsubstituted aryl group; and X.sup.-
 represents an acid anion;
 ##STR8##
 wherein, in the general formula (6), R.sup.17 and R.sup.18 each
 independently represents a substituted or unsubstituted alkyl group, or a
 substituted or unsubstituted aryl group; and X.sup.- represents an acid
 anion.
 Further, in a heat-sensitive recording material of the present invention,
 the diazonium salt compound is preferably encapsulated in microcapsules,
 and it is further preferable that capsule walls of the microcapsules
 comprise polyurethane and/or polyurea as components.
 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
 A pyrrolo[1,2-a]pyrimidine compound of the present invention will be
 described in detail hereinafter. The pyrrolo[1,2-a]pyrimidine compound of
 the present invention has characteristics in which when it is coupled as a
 coupler with a diazonium salt compound, not only are excellent hue of a
 cyan system having little yellow light absorption and sufficient density
 of formed color obtained, but also light resistance is improved, and
 particularly excellent results regarding light resistance are obtained
 even under strict conditions, resulting in significantly reduced coloring
 of background portions.
 The pyrrolo[1,2-a]pyrimidine compound of the present invention is a
 compound represented by one of the general formulae (1), (2) and (3).
 In the formulae (1) and (2), R.sup.1 and R.sup.2 each independently
 represents a hydrogen atom, halogen atom, aryl group, alkyl group, cyano
 group, acyl group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl
 group, alkylsulfonyl group or arylsulfonyl group. R.sup.3 represents an
 electron attractive group whose value of Hammett's substituent constant
 .sigma..sub.p is equal to or larger than 0.20. X represents CO or
 SO.sub.2.
 Of the above values, as the substituents represented by R.sup.1 and
 R.sup.2, at least one of R.sup.1 and R.sup.2 is preferably an electron
 attractive group whose value of Hammett's substituent constant
 .sigma..sub.p is equal to or larger than 0.20, and it is further
 preferable that at least one of R.sup.1 and R.sup.2 is an electron
 attractive group whose value of .sigma..sub.p is equal to or larger than
 0.35.
 Examples of the electron attractive groups whose value of .sigma..sub.p is
 equal to or larger than 0.20 preferably include, but are not limited to, a
 cyano group (whose .sigma..sub.p value is 0.66), perfluoroalkyl group (for
 example, trifluoromethyl group whose .sigma..sub.p value is 0.54), acyl
 group (for example, acetyl group whose .sigma..sub.p value is 0.50,
 benzoyl group whose .sigma..sub.p value is 0.43), carbamoyl group (whose
 .sigma..sub.p value is 0.36), alkoxycarbonyl group (for example,
 ethoxycarbonyl group whose .sigma..sub.p value is 0.45) and the like.
 Examples of the halogen atom include a fluorine atom, chlorine atom,
 bromine atom and the like, and a fluorine atom and chlorine atom are
 further preferable.
 Examples of the electron attractive groups whose value of Hammett's
 substituent constant .sigma..sub.p is equal to or larger than 0.20 and
 that are represented by R.sup.3 preferably include, but are not limited
 to, an aryl group, cyano group, acyl group, carbamoyl group,
 alkoxycarbonyl group, aryloxycarbonyl group, alkylsulfonyl group,
 arylsulfonyl group, alkylphosphoryl group, arylphosphoryl group,
 perfluoroalkyl group and the like.
 Of the substituents represented by R.sup.1 through R.sup.3, the aryl group
 may be substituted further by an alkyl group, alkoxy group, aryloxy group,
 halogen atom, nitro group, cyano group, substituted carbamoyl group,
 substituted sulfamoyl group, substituted amino group, substituted
 oxycarbamoyl group, substituted oxysulfonyl group, alkylthio group,
 arylthio group, alkylsulfonyl group, arylsulfonyl group, aryl group,
 hydroxy group, acyl group, acyloxy group, substituted sulfonyloxy group,
 substituted aminocarbonyloxy group, substituted phosphoryloxy group or the
 like.
 When R.sup.1 and R.sup.2 each independently represents an aryl group, an
 aryl group having 6 through 30 carbon atoms is preferable as the aryl
 group, and examples thereof include not only a phenyl group,
 2-methylphenyl group, 2-chlorophenyl group, 2-methoxyphenyl group,
 2-ethoxyphenyl group, 2-propoxyphenyl group, 2-isopropoxyphenyl group,
 2-butoxyphenyl group, 2-(2-ethylhexyloxy)phenyl group, 2-octyloxyphenyl
 group, 2-undecyloxyphenyl group, 2-trifluoromethylphenyl group,
 2-(2-ethylhexyloxy)-5-chlorophenyl group,
 2-(2-ethylhexyloxy)-3,5-dichlorophenyl group,
 3-(2,4-di-t-pentylphenoxyethoxy)phenyl group,
 2-(dibutylaminocarbonylethoxy)phenyl group, 2,4-dichlorophenyl group,
 2,5-dichlorophenyl group, 2,4,6-trimethylphenyl group, 3-chlorophenyl
 group, 3-nitrophenyl group, 3-cyanophenyl group, 3-trifluoromethylphenyl
 group, 3-methoxyphenyl group, 3-ethoxyphenyl group, 3-butoxyphenyl group,
 3-(2-ethylhexyloxy)phenyl group, 3,4-dichlorophenyl group,
 3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group, 3,5-dibutoxyphenyl
 group, 3-octyloxyphenyl group, 3-(dibutylaminocarbonylmethoxy)phenyl
 group, 3-(di-2-ethylhexylaminocarbonylmethoxy)phenyl group,
 3-dodecyloxyphenyl group, 4-chlorophenyl group, 4-cyanophenyl group,
 4-nitrophenyl group, 4-trifluoromethylphenyl group, 4-methoxyphenyl group,
 4-ethoxyphenyl group, 4-isopropoxyphenyl group, 4-butoxyphenyl group,
 4-(2-ethylhexyloxy)phenyl group, 4-isopentyloxyphenyl group,
 4-(octadecyloxy)phenyl group, 4-benzylphenyl group, 4-aminosulfonylphenyl
 group, 4-N,N-dibutylaminosulfonylphenyl group, 4-ethoxycarbonylphenyl
 group, 4-(2-ethylhexyloxycarbonyl)phenyl group, 4-t-octylphenyl group,
 4-fluorophenyl group, 3-acetylphenyl group, 2-acetylaminophenyl group,
 2,4-di-t-pentylphenyl group, 4-(2-ethylhexyloxy)carbonylphenyl group,
 4-methylthiophenyl group and 4-(4-chlorophenylthio)phenyl group, but also
 hydroxyphenyl group, phenylsulfonylphenyl group, phenylsulfonyloxyphenyl
 group, phenylcarbonyloxyphenyl group, dimethylaminocarbonyloxyphenyl
 group, butylcarbonyloxyphenyl group and the like.
 When R.sup.3 represents an aryl group, an aryl group having 6 through 30
 carbon atoms is preferable as the aryl group, and examples thereof include
 a 3-nitrophenyl group, 4-nitrophenyl group, 4-cyanophenyl group,
 4-trifluoromethylphenyl group, 4-methylsulfonylphenyl group,
 4-ethylsulfonylfphenyl group, 4-octylsulfonylphenyl group,
 4-phenylsulfonylphenyl group, pentafluorophenyl group, pentachlorophenyl
 group and the like.
 Of the substituents represented by R.sup.1 and R.sup.2, the alkyl group may
 be linear or branched, and may have an unsaturated bond. Further, the
 above alkyl group may be substituted by an alkoxy group, aryloxy group,
 alkoxycarbonyl group, aryloxycarbonyl group, aryl group, hydroxy group,
 halogen atom or the like. Likewise, the aryl group described above may
 further be substituted by an alkyl group, alkoxy group, nitro group, cyano
 group, hydroxy group or halogen atom.
 When R.sup.1 and R.sup.2 each independently represents an alkyl group, an
 alkyl group having 1 through 30 carbon atoms is preferable as the alkyl
 group, and examples thereof include a methyl group, trifluoromethyl group,
 ethyl group, butyl group, hexyl group, octyl group, 2-ethylhexyl group,
 decyl group, dodecyl group, octadecyl group, propyl group, isopropyl
 group, isobutyl group, sec-butyl group, t-butyl group, pentyl group,
 1-ethylpentyl group, cyclopentyl group, cyclohexyl group, isopentyl group,
 heptyl group, nonyl group, undecyl group, propenyl group, heptadecenyl
 group, t-octyl group, ethoxycarbonylmethyl group, butoxycarbonylmethyl
 group, 2-ethylhexyloxycarbonylmethyl group, 1-(ethoxycarbonyl)ethyl group,
 2',4'-diisopentylphenyloxymethyl group, 2',4'-di-t-butylphenyloxymethyl
 group, ethoxycarbonylethyl group, 2-ethylhexyloxycarbonylethyl group,
 butyldecyloxycarbonylethyl group, dibutylaminocarbonylmethyl group,
 dibenzylaminocarbonylethyl group, ethyloxycarbonylpropyl group,
 2-ethylhexyloxycarbonylpropyl group, 2,4-di-t-amylphenyloxypropyl group,
 1-(2',4'-di-t-amylphenyloxy) propyl group, 2,4-di-t-butylphenyloxypropyl
 group, acetylaminoethyl group, N,N-dihexylaminocarbonylethyl group,
 2,4-di-t-amyloxyethyloxycarbonylpropyl group, isostearyloxycarbonylpropyl
 group, 1-(2,4-di-t-pentylphenyloxy)propyl group,
 2,4-di-t-pentylphenyloxyethyloxycarbonylpropyl group,
 naphthyloxyethyloxycarbonylethyl group,
 N-methyl-N-phenylethyloxycarbonylethyl group, methanesulfonylaminopropyl
 group and the like.
 Of the substituents represented by R.sup.1 through R.sup.3, an acyl group
 having 2 through 20 carbon atoms is preferable as the acyl group, and
 examples thereof include an acetyl group, propanoyl group, butanoyl group,
 hexanoyl group, octanoyl group, 2-ethylhexanoyl group, decanoyl group,
 dodecanoyl group, octadecanoyl group, 2-cyanopropanoyl group,
 1,1-dimethylpropanoyl group, benzoyl group, 2-(2,4-di-t-pentylphenyloxy)
 butanoyl group, phenoxyacetyl group and the like.
 Of the substituents represented by R.sup.1 through R.sup.3, the carbamoyl
 group may be a substituted or unsubstituted carbamoyl group, and examples
 thereof include a carbamoyl group, N-alkylcarbamoyl group, N-arylcarbamoyl
 group, N-acylcarbamoyl group, N-alkoxycarbonylcarbamoyl group,
 N-aryloxycarbonylcarbamoyl group, N-alkylsulfonylcarbamoyl group,
 N-arylsulfonylcarbamoyl group, N,N-dialkylcarbamoyl group,
 N,N-diarylcarbamoyl group, N-alkyl-N-arylcarbamoyl group and the like.
 As the substituted carbamoyl group, a substituted carbamoyl group having 1
 through 30 carbon atoms is preferable, and examples thereof include an
 N-methylcarbamoyl group, N-ethylcarbamoyl group, N-propylcarbamoyl group,
 N-butylcarbamoyl group, N-hexylcarbamoyl group, N-cyclohexylcarbamoyl
 group, N-octylcarbamoyl group, N-2-ethylhexylcarbamoyl group,
 N-decylcarbamoyl group, N-octadecylcarbamoyl group, N-phenylcarbamoyl
 group, N-2-methylphenylcarbamoyl group, N-2-chlorophenylcarbamoyl group,
 N-2-methoxyphenylcarbamoyl group, N-2-isopropoxyphenylcarbamoyl group,
 N-2-(2-ethylhexyloxy)phenylcarbamoyl group, N-3-chlorophenylcarbamoyl
 group, N-3-nitrophenylcarbamoyl group, N-3-cyanophenylcarbamoyl group,
 N-4-methoxyphenylcarbamoyl group, N-4-(2-ethylhexyloxy)phenylcarbamoyl
 group, N-4-cyanophenylcarbamoyl group, N-acetylcarbamoyl group,
 N-benzoylcarbamoyl group, N-methoxycarbonylcarbamoyl group,
 N-ethoxycarbonylcarbamoyl group, N-butoxycarbonylcarbamoyl group,
 N-phenoxycarbonylcarbamoyl group, N-methylsulfonylcarbamoyl group,
 N-ethylsulfonylcarbamoyl group, N-isopropylsulfonylcarbamoyl group,
 N-butylsulfonylcarbamoyl group, N-octylsulfonylcarbamoyl group,
 N-phenylsulfonylcarbamoyl group, N-(4-methylphenyl)sulfonylcarbamoyl
 group, N-(4-chlorophenyl)sulfonylcarbamoyl group,
 N-(4-methoxyphenyl)sulfonylcarbamoyl group,
 N-[4-(2-ethylhexyloxy)phenyl]sulfonylcarbamoyl group,
 N,N-dimethylcarbamoyl group, N,N-dibutylcarbamoyl group,
 N,N-diphenylcarbamoyl group, N-methyl-N-phenylcarbamoyl group and the
 like.
 Of the substituents represented by R.sup.1 through R.sup.3, an
 alkoxycarbonyl group having 2 through 20 carbon atoms is preferable as the
 alkoxycarbonyl group, and examples thereof include a methoxycarbonyl
 group, ethoxycarbonyl group, propoxycarbonyl group, butoxycarbonyl group,
 hexyloxycarbonyl group, 2-ethylhexyloxycarbonyl group, octyloxycarbonyl
 group, decyloxycarbonyl group, octadecyloxycarbonyl group,
 phenyloxyethyloxycarbonyl group, phenyloxypropyloxycarbonyl group,
 2,4-di-t-amylphenyloxyethylcarbonyl group,
 2,6-di-t-butyl-4-methylcyclohexyloxycarbonyl group, isostearyloxycarbonyl
 group and the like.
 Of the substituents represented by R.sup.1 through R.sup.3, an
 aryloxycarbonyl group having 7 through 30 carbon atoms is preferable as
 the aryloxycarbonyl group, and examples thereof include a
 2-methylphenyloxycarbonyl group, 2-chlorophenyloxycarbonyl group,
 2,6-dimethylphenyloxycarbonyl group, 2,4,6-trimethylphenyloxycarbonyl
 group, 2-methoxyphenyloxycarbonyl group, 2-butoxyphenyloxycarbonyl group,
 3-cyanophenyloxycarbonyl group, 3-nitrophenyloxycarbonyl group,
 2,2-ethylhexylphenyloxycarbonyl group,
 3-(2-ethylhexyloxy)phenyloxycarbonyl group, 4-fluorophenyloxycarbonyl
 group, 4-chlorophenyloxycarbonyl group, 4-cyanophenyloxycarbonyl group,
 4-butoxyphenyloxycarbonyl group and the like.
 Of the substituents represented by R.sup.1 through R.sup.3, an
 alkylsulfonyl group having 1 through 20 carbon atoms is preferable as the
 alkylsulfonyl group, and examples thereof include a methylsulfonyl group,
 ethylsulfonyl group, propylsulfonyl group, isopropylsulfonyl group,
 butylsulfonyl group, hexylsulfonyl group, cyclohexylsulfonyl group,
 octylsulfonyl group, 2-ethylhexylsulfonyl group, decanoylsulfonyl group,
 dodecanoylsulfonyl group, octadecanoylsulfonyl group, cyanomethylsulfonyl
 group and the like.
 Of the substituents represented by R.sup.1 through R.sup.3, an arylsulfonyl
 group having 6 through 30 carbon atoms is preferable as the arylsulfonyl
 group, and examples thereof include a phenylsulfonyl group,
 1-naphthylsulfonyl group, 2-naphthylsulfonyl group, 2-chlorophenlsulfony
 group, 2-methylphenylsulfonyl group, 2-methoxyplhenylsulfonyl group,
 2-butoxyphelnylsulfonyl group, 3-chlorophenylsulfonyl group,
 3-trifluoromethylplienylsulfonyl group, 3-cyanophenylsulfonyl group,
 3-(2-ethylhexyloxy)phenylsulfonyl group, 3-nitrophenylsulfonyl group,
 4-fluorophenylsulfonyl group, 4-chlorophenylsulfonyl group,
 4-methylphenylsulfonyl group, 4-cyanophenylsulfonyl group,
 4-butoxyphenylsulfonyl group, 4-(2-ethylhexyloxy)phenylsulfonyl group,
 4-octadecylphenylsulfonyl group and the like.
 Of the substituents represented by R.sup.3, an alkylphosphoryl group having
 2 through 40 carbon atoms is preferable as the alkylphosphoryl group, and
 examples thereof include a methylphosphoryl group, ethylphosphoryl group,
 propylphosphoryl group, isopropylphosphoryl group, butylphosphoryl group,
 isobutylphosphoryl group, sec-butylphosphoryl group, t-butylphosphoryl
 group, pentylphosphoryl group, isopentylphosphoryl group, hexylphosphoryl
 group, heptylphosphoryl group, octylphosphoryl group,
 2-ethylhexylphosphoryl group, decylphosphoryl group, dodecylphosphoryl
 group, octadecylphosphoryl group, ethoxycarbonylmethylphosphoryl group,
 2-ethylhexyloxycarbonylmethylphosphoryl group,
 aminocarbonylmethylphosphoryl group,
 N,N-dibutylaminocarbonylmethylphosphoryl group,
 N-methylaminocarbonylmethylphosphoryl group,
 N-ethylaminocarbonylmethylphosphoryl group,
 N-octylaminocarbonylmethylphosphoryl group, benzylphosphoryl group and the
 like.
 Of the substituents represented by R.sup.3, an arylphosphoryl group having
 12 through 50 carbon atoms is preferable as the arylphosphoryl group, and
 examples thereof include a phenylphosphoryl group, 1-naphthylphosphoryl
 group, 2-naphthylphosploryl group, 2-chlorophenylphosphory group,
 2-methylphenylphosphoryl group, 2-methoxyphenylphosphoryl group, 2-butoxy
 phenylphosphoryl group, 3-chlorophenylphosphoryl group,
 3-trefluoromethylphenylphosphoryl group, 3-cyanophenylphosphoryl group,
 3-(2-ethylhexyloxy)phenylphosphoryl group, 3-nitrophenytphosphoryl group,
 4-fluorophenylphosphoryl group, 4-cyanophenylphosphoryl group,
 4-butoxyphenylphosphoryl group, 4-(2-ethylhexyloxy)phenylphosphoryl group,
 4-octadecylphenylphosphoryl group and the like.
 Of the substituent represented by R.sup.3, a perfluoroalkyl group having 1
 through 20 carbon atoms is preferable as the perfluoroalkyl group, and
 examples thereof include a trifluoromethyl group, pentafluoroethyl group,
 heptafluoropropyl group, nonafluorobutyl group and the like.
 Of the above substituents, an alkyl group or aryl group is preferable as
 the substltuents represented by R.sup.1, and an aryl group is further
 preferable.
 A cyano group or alkoxycarbonyl group is preferable as the substituents
 represented by R.sup.2, and an alkoxycarbonyl group is further preferable.
 A carbamoyl group is preferable as the substituents represented by R.sup.3,
 and an N-arylsulfonylcarbamoyl group is further preferable.
 Specific examples of the pyrrolo[1,2-a]pyrimidine compound represented by
 the general formulae (1) and (2) are given below. However, the
 pyrrolo[1,2-a]pyrimidine of the present invention is not limited to the
 followng examples. It is to be noted that R.sup.1 through R.sup.3 and X in
 the following Tables 1 through 7 represent symbols in the general formulae
 (1) and (2).
 TABLE 1
 ##STR9##
 No. R.sup.1 R.sup.2 R.sup.3
 1 ##STR10## --CN
 --COCH.sub.3
 2 ##STR11## --CN --COC.sub.3
 H.sub.7 (n)
 3 ##STR12## --CN ##STR13##
 4 ##STR14## --CN ##STR15##
 5 ##STR16## --CN ##STR17##
 6 ##STR18## ##STR19##
 --COCH.sub.3
 7 ##STR20## ##STR21## ##STR22##
 8 ##STR23## ##STR24## ##STR25##
 TABLE 2
 No. R.sup.1 R.sup.2
 R.sup.3
 9 ##STR26## ##STR27##
 ##STR28##
 10 ##STR29## ##STR30##
 ##STR31##
 11 ##STR32## ##STR33##
 ##STR34##
 12 ##STR35## ##STR36##
 ##STR37##
 13 ##STR38## ##STR39##
 ##STR40##
 14 ##STR41## ##STR42##
 ##STR43##
 15 ##STR44## ##STR45##
 ##STR46##
 16 ##STR47## ##STR48##
 ##STR49##
 17 ##STR50## ##STR51##
 ##STR52##
 18 ##STR53## ##STR54##
 ##STR55##
 TABLE 3
 No. R.sup.1 R.sup.2
 R.sup.3
 19 ##STR56## --CO.sub.2 CH.sub.3
 ##STR57##
 20 ##STR58## --CO.sub.2 C.sub.2 H.sub.5
 ##STR59##
 21 ##STR60## --CO.sub.2 CH.sub.3
 ##STR61##
 22 ##STR62## --CO.sub.2 C.sub.2 H.sub.5
 ##STR63##
 23 ##STR64## --CO.sub.2 C.sub.3 H.sub.7 (n)
 ##STR65##
 24 ##STR66## --CO.sub.2 C.sub.3 H.sub.7 (i)
 ##STR67##
 25 ##STR68## ##STR69##
 ##STR70##
 26 ##STR71## ##STR72## --CONHCO.sub.2
 C.sub.2 H.sub.5
 27 ##STR73## ##STR74##
 ##STR75##
 28 --CF.sub.3 ##STR76##
 ##STR77##
 TABLE 4
 No. R.sup.1 R.sup.2 R.sup.3
 29 ##STR78## --CONH.sub.2 ##STR79##
 30 ##STR80## --CON(CH.sub.3).sub.2 ##STR81##
 31 ##STR82## --CONHCH.sub.3 ##STR83##
 32 ##STR84## ##STR85## ##STR86##
 33 ##STR87## ##STR88## ##STR89##
 34 ##STR90## ##STR91## ##STR92##
 35 ##STR93## --SO.sub.2 CH.sub.3 ##STR94##
 36 ##STR95## ##STR96## ##STR97##
 37 ##STR98## ##STR99## --CO.sub.2 C.sub.2
 H.sub.5
 38 ##STR100## ##STR101## --CO.sub.2 C.sub.8
 H.sub.17 (n)
 TABLE 5
 No. R.sup.1 R.sup.2 R.sup.3
 39 ##STR102## ##STR103## ##STR104##
 40 ##STR105## ##STR106## ##STR107##
 41 ##STR108## ##STR109## --SO.sub.2 CH.sub.3
 42 ##STR110## ##STR111## ##STR112##
 43 ##STR113## ##STR114## ##STR115##
 44 ##STR116## ##STR117## ##STR118##
 45 ##STR119## ##STR120## ##STR121##
 46 ##STR122## ##STR123## --CF.sub.3
 47 ##STR124## ##STR125## --CN
 TABLE 6
 ##STR126##
 No. R.sup.1 R.sup.2 X
 48 ##STR127## ##STR128## ##STR129##
 49 ##STR130## ##STR131## ##STR132##
 50 ##STR133## ##STR134## ##STR135##
 51 ##STR136## ##STR137## ##STR138##
 52 ##STR139## ##STR140## ##STR141##
 53 ##STR142## ##STR143## ##STR144##
 54 ##STR145## ##STR146## ##STR147##
 55 ##STR148## ##STR149## ##STR150##
 TABLE 7
 No. R.sup.1 R.sup.2 X
 56 ##STR151## ##STR152## ##STR153##
 57 ##STR154## ##STR155## ##STR156##
 58 ##STR157## --SO.sub.2 CH.sub.3 ##STR158##
 59 ##STR159## --CO.sub.2 C.sub.2 H.sub.5 ##STR160##
 60 ##STR161## --CO.sub.2 C.sub.2 H.sub.5 ##STR162##
 61 ##STR163## --CO.sub.2 C.sub.2 H.sub.5 ##STR164##
 62 ##STR165## --CO.sub.2 C.sub.2 H.sub.5 ##STR166##
 63 ##STR167## --CO.sub.2 C.sub.2 H.sub.5 ##STR168##
 64 ##STR169## --CO.sub.2 C.sub.2 H.sub.5 ##STR170##
 Next, a method of preparing the pyrrolo[1,2-a]pyrimidine compounds
 represented by the general formulae (1) and (2), respectively, will be
 described.
 The compound of the present invention represented by the general formula
 (1) can be obtained by reacting the pyrrolo[1,2-a]pyrimidine compound
 having an amino group (hereinafter, simply referred to as "amino structure
 A") with R.sup.3 --X (X=halogen) (the following reaction formula (1)).
 ##STR171##
 Further, when R.sup.3 is a carbamoyl group, isocyanate can be used Instead
 of halide as a reaction agent (the following reaction formula (2)).
 ##STR172##
 The compound of the present inventioin represented by the general formula
 (2) can be obtained by first reacting the amino structure A with
 chlorosulfonylisocyanate or chlorocarbonylssocyanate, to which a base is
 added thereafter for causing a reaction (see the following reaction
 formula (3)).
 ##STR173##
 The amount of halide (R.sup.3 --X) and isocyanate used in the reactions
 shown in the reaction formulae (1) and (2) is approximately 1 through 10
 equivalent and preferably 1 through 5 equivalent in relation to 1
 equivalent of the amino structure used as raw material.
 As the solvent for dissolving the amino structure A, various types of
 solvents or a mixture thereof can be used, examples of the solvents
 including aromatic hydrocarbons such as benzene, toluene and xylene, chain
 or cyclic aliphatic hydrocarbons such as pentane, hexane, heptane and
 cyclohexane, ethers such as diethyl ether, duisopropyl ether,
 tetrahydrofuran, dioxane and ethyleneglycoldimethylether, halogenated
 hydrocarbons such as dichloromethane, chloroform, 1,2-dichloroethane,
 nitriles such as acetonitrile, acetic esters such as methyl acetate and
 ethyl acetate, N,N-dimethylformamide, N,N-dimethylacetamide,
 dimethylsulfoxide and the like. The amount to be used of the above
 solvents is not particularly limited.
 Examples of a method for running the reactions include a method in which
 halide or isocyanate is dripped or added in portions into a solution of
 the amino structure A.
 The temperature at which the reactions are run is normally selected from a
 range of from room temperature to the boiling point of the solvent, and is
 preferably from 20 through 70.degree. C.
 The time of the reactions is normally approximately of from 0.5 through 24
 hours, which varies depending on the reaction temperature.
 A catalyst may be added to the reactions as needed so as to reduce the
 reaction time and to improve the yield.
 Examples of the catalyst include a boron trifluoride diethyl ether complex,
 a tin catalyst such as dibutyltindiacetate, aluminum chloride and the
 like.
 The amount of the catalyst to be used is approximately up until 0.5
 equivalent and is preferably approximately up until 0.05 equivalent in
 relation to 1 equivalent of the amino structure A.
 After the reactions are completed, the target object can be derived by
 conventional after-treatment operations such as extraction, and further,
 refining can be carried out, as needed, by refining means such as silica
 gel column chromatography and recrystallization.
 When the boiling point of the solvent used for the reactions is low, the
 extracting operation can be omitted and the refining can be carried out
 after the reaction liquid is concentrated.
 The first stage of the reaction shown by the reaction formula (3), in other
 words, the addition reaction of isocyaniate, can be carried out under the
 same conditions as the ones shown by the reaction formulae (1) and (2).
 The generated intermediate is not to be isolated, and the target object
 can be obtained by treating it with a base (the second stage).
 Examples of the base include organic bases such as triethylamine, pyridine
 and DBU, alkali metal hydrides such as sodium hydride and potassium
 hydride, metal alcoholates such as sodium methylate, sodium ethylate and
 potassium butylate, alkali metal hydroxides such as sodium hydroxide and
 potassium hydroxide, alkaline earth metal hydroxides such as calcium
 hydroxide and magnesium hydroxide, alkali metal carbonates such as sodium
 hydrogencarbonate, potassium carbonate and potassium hydrogencarbonate,
 alkali metallic salts of lower carboxylic acids such as sodium formate and
 sodium acetate and the like. Of the above bases, organic bases such as
 triethylamine and pyridine, and alkali metal hydrides such as sodium
 hydroxide are preferable.
 The amount of the base to be used is preferably 1 through 2 equivalent in
 relation to 1 equivalent of the amino structure A.
 The amino structure A used as raw material can be synthesized by the
 following method described in Japanese Patent Application No. 10-210029.
 Further, an amino-pyrrole derivative can be synthesized by the method
 described in Japanese Patent Application No. 9-63619 and the like.
 ##STR174##
 In the general formula (3), R.sup.19 and R.sup.20 each independently
 represents a hydrogen atom, halogen atom, aryl group, alkyl group, cyano
 group, acyl group, substituted carbamoyl group, alkoxycarbonyl group,
 aryloxycarbonyl group, acyloxy group, alkoxy group, aryloxy group,
 alkylthio group, arylthio group, substituted sulfamoyl group,
 alkylsulfonyl group, arylsulfonyl group, alkylphosphoryl group,
 arylphosphoryl group, or substituted amino group.
 R.sup.30 and R.sup.40 each independently represents a hydrogen atom, alkyl
 group, aryl group, cycloalkyl group, piperidyl group, acyl group,
 --C.sub.n H.sub.2n N(R.sup.50)(R.sup.60) or --C.sub.m H.sub.2m XC.sub.1
 H.sub.21 N(R.sup.70)(R.sup.80).
 R.sup.50 through R.sup.80 each independently represents a hydrogen atom,
 alkyl group or aryl group.
 X represents an oxygen atom, sulfur atom, or N(R.sup.90)--. R.sup.90
 represents a hydrogen atom, alkyl group or aryl group. R.sup.30 and
 R.sup.40, or R.sup.50 and R.sup.60, or R.sup.70 and R.sup.80, or R.sup.70
 and R.sup.90, or R.sup.80 and R.sup.90 may combine with each other to form
 a ring, and in the case of ring formation, they may contain a hetero atom.
 n, m and 1 represent integers from 1 through 12.
 Of the above values, as the substituents represented by R.sup.19 and
 R.sup.20, at least one of R.sup.19 and R.sup.20 is preferably an electron
 attractive group whose value of Hammett's substituent constant
 .sigma..sub.p is equal to or larger than 0.20, and it is further
 preferable that at least one of R.sup.19 and R.sup.20 is an electron
 attractive group whose value of .sigma..sub.p is equal to or larger than
 0.35.
 Examples of the electron attractive groups whose value of .sigma..sub.p is
 equal to or larger than 0.20 preferably include, but are not limited to, a
 cyano group (whose .sigma..sub.p value is 0.66), perfluoroalkyl group (for
 example, trifluoromethl group whose .sigma..sub.p value is 0.54), acyl
 group (for example, acetl group whose .sigma..sub.p value is 0.50, benzoyl
 group whose .sigma..sub.p value is 0.43), carbamoyl group (whose
 .sigma..sub.p value is 0.36) and the like.
 Examples of the halogen atom include a fluorine atom, chlorine atom,
 bromine atom and the like, and a fluorine atom and chlorine atom are
 further preferable.
 Of the substituents represented by R.sup.19 and 20, the aryl group may be
 substituted further by an alkyl group, alkoxy group, aryloxy group,
 halogen atom, nitro group, cyano group, substituted carbamoyl group,
 substituted sulfamoyl group, substituted amino group, substituted
 oxycarbamoyl group, substituted oxysulfonyl group, alkylthio group,
 arylthio group, alkylsulfonyl group, arylsulfonyl group, aryl group,
 hydroxy group, acyl group, acyloxy group, substituted sulfonyloxy group,
 substituted aminocarbonyloxy group, or substituted phosphoryloxy group.
 As the aryl group, an aryl group having 6 through 30 carbon atoms is
 preferable, and examples thereof include not only a phenyl group,
 2-methylphenyl group, 2-chlorophenyl group, 2-methoxyphenyl group,
 2-ethoxyphenyl group, 2-propoxyphenyl group, 2-isopropoxyphenyl group,
 2-butoxyphenyl group, 2-(2-ethylhexyloxy)phenyl group, 2-octyloxyphenyl
 group, 2-undecyloxyphenyl group, 2-trifluoromethylphenyl group,
 2-(2-ethylhexyloxy)-5-chlorophenyl group,
 2-(2-ethylhexyloxy)-3,5-dichlorophenyl group,
 3-(2,4-di-t-pentylphenoxyethoxy)phenyl group,
 2-(dibutylaminocarbonylethoxy)phenyl group, 2,4-dichlorophenyl group,
 2,5-dichlorophenyl group, 2,4,6-trimethylphenyl group, 3-chlorophenyl
 group, 3-nitrophenyl group, 3-cyanophenyl group, 3-trifluoromethylphenyl
 group, 3-methoxypheny,l group, 3-ethoxyphenyl group, 3-butoxyphenyl group,
 3-(2-ethylhexyloxy)phenyl group, 3,4-dichlorophenyl group,
 3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group, 3,5-dibutoxyphenyl
 group, 3-octyloxyphenyl group, 3-(dibutylaminocarbonylmethoxy)phenyl
 group, 3-(di-2-ethylhexylaminocarbonylmethoxy)phenyl group,
 3-dodecyloxyphenyl group, 4-chlorophenyl group, 4-cyanophenyl group,
 4-nitrophenyl group, 4-trifluoromethylphenyl group, 4-methoxyphenyl group,
 4-ethoxyphenyl group, 4-isopropoxyphenyl group, 4-butoxyphenyl group,
 4-(2-ethylhexyloxy)phenyl group, 4-isopentyloxyphenyl group,
 4-(octadecyloxy)phenyl group, 4-benzylphenyl group, 4-aminosulfonylphenyl
 group, 4-N,N-dibutylaminosulfonylphenyl group, 4-ethoxycarbonylphenyl
 group, 4-(2-ethylhexyloxycarbonyl)phenyl group, 4-t-octylphenyl group,
 4-fluorophenyl group, 3-acetylphenyl group, 2-acetylaminophenyl group,
 2,4-di-t-pentylphenyl group, 4-(2-ethylhexyloxy)carbonylphenyl group,
 4-methylthiophenyl group and 4-(4-chlorophenylthio)phenyl group, but also
 hydroxyphenyl group, phenylsulfonylphenyl group, phenylsulfonyloxyphenyl
 group, phenylcarbonyloxyphenyl group, dimethylaminocarbonyloxyphenyl
 group, butylcarbonyloxyphenyl group and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, the alkyl group
 may be linear or branched, and may have an unsaturated bond. Further, the
 above alkyl group may be substituted by an alkoxy group, aryloxy group,
 alkoxycarbonyl group, aryloxycarbonyl group, aryl group, hydroxy group,
 halogen atom or the like. Likewise, the aryl group described above may
 further be substituted by an alkyl group, alkoxy group, nitro group, cyano
 group, hydroxy group or a halogen atom.
 As the alkyl group, an alkyl group having 1 through 30 carbon atoms is
 preferable, and examples thereof include a methyl group, trifluoromethyl
 group, ethyl group, butyl group, hexyl group, octyl group, 2-ethylhexyl
 group, decyl group, dodecyl group, octadecyl group, propyl group,
 isopropyl group, isobutyl group, sec-butyl group, t-butyl group, pentyl
 group, 1-ethylpentyl group, cyclopentyl group, cyclohexyl group, isopentyl
 group, heptyl group, nonyl group, undecyl group, propenyl group,
 heptadecenyl group, t-octyl group, ethoxycarbonylmethyl group,
 butoxycarbonylmethyl group, 2-ethylhexyloxycarbonylmethyl group,
 1-(ethoxycarbonyl)ethyl group, 2',4'-diisopentylphenyloxymethyl group,
 2',4'-di-t-butylphenyloxymethyl group, ethoxycarbonylethyl group,
 2-ethylhexyloxycarbonylethyl group, butyldecyloxycarbonylethyl group,
 dibutylaminocarbonylmethyl group, dibenzylaminocarbonylethyl group,
 ethyloxycarbonylpropyl group, 2-ethylhexyloxycarbonylpropyl group,
 2,4-di-t-amylphenyloxypropyl group, 1-(2',4'-di-t-amylphenyloxy) propyl
 group, 2,4-di-t-butylphenyloxypropyl group, acetylaminoethyl group,
 N,N-dihexylaminocarbonylethyl group,
 2,4-di-t-amyloxyethyloxycarbonylpropyl group, isostearyloxycarbonylpropyl
 group, 1-(2,4-di-t-pentylphenyloxy)propyl group,
 2,4-di-t-pentylphenyloxyethyloxycarbonylpropyl group,
 naphthyloxyethyloxycarbonylethyl group,
 N-methyl-N-phenylethyloxycarbonylethyl group, methanesulfonylaminopropyl
 group and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, an acyl group
 having 2 through 20 carbon atoms is preferable as the acyl group, and
 examples thereof include an acetyl group, propanoyl group, butanoyl group,
 hexanoyl group, octanoyl group, 2-ethylhexanoyl group, decanoyl group,
 dodecanoyl group, octadecanoyl group, 2-cyanopropanoyl group,
 1,1-dimethylpropanoyl group and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, the substituted
 carbamoyl group includes a carbamoyl group, N-alkylcarbamoyl group,
 N-arylcarbamoyl group, N,N-dialkylcarbamoyl group, N,N-diarylcarbamoyl
 group, N-alkyl-N-arylcarbamoyl group and the like.
 As the substituted carbamoyl group, a substituted carbamoyl group having 1
 through 30 carbon atoms is preferable, and examples thereof include an
 N-methylcarbamoyl group, N-ethylcarbamoyl group, N-propylcarbamoyl group,
 N-butylcarbamoyl group, N-hexylcarbamoyl group, N-cyclohexylcarbamoyl
 group, N-octylcarbamoyl group, N-2-ethylhexylcarbamoyl group,
 N-decylcarbamoyl group, N-octadecylcarbamoyl group, N-phenylcarbamoyl
 group, N-2-methylphenylcarbamoyl group, N-2-chlorophenylcarbamoyl group,
 N-2-methoxyphenylcarbamoyl group, N-2-isopropoxyphenylcarbamoyl group,
 N-2-(2-ethylhexyloxy)phenylcarbamoyl group, N-3-chlorophenylcarbamoyl
 group, N-3-nitrophenylcarbamoyl group, N-3-cyanophenylcarbamoyl group,
 N-4-methoxyphenylcarbamoyl group, N-4-(2-ethylhexyloxy)phenylcarbamoyl
 group, N-4-cyanophenylcarbamoyl group, N-methyl-N-phenylcarbamoyl group,
 N,N-dimethylcarbamoyl group, N,N-dibutylcarbamoyl group,
 N,N-diphenylcarbamoyl group and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, an alkoxycarbonyl
 group having 2 through 20 carbon atoms is preferable as the alkoxycarbonyl
 group, and examples thereof include a methoxycarbonyl group,
 ethoxycarboiyl group, propoxycarbonyl group, butoxycarbonyl group,
 hexyloxycarbonyl group, 2-ethylhexyloxycarbonyl group, octyloxcarbonyl
 group, decyloxycarbonyl group, octadecyloxycarbonyl group,
 phenyloxyethyloxycarbonyl group, phenyloxypropyloxycarbonyl group,
 2,4-di-t-amylphenyloxyethylcarbonyl group,
 2,6-di-t-butyl-4-methylcyclohexyloxycarbonyl group, isostearyloxycarbonyl
 group and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, an
 aryloxycarbonyl group having 7 through 30 carbon atoms is preferable as
 the aryloxycarbonyl group, and examples thereof include a
 2-methylphenyloxycarbonyl group, 2-chlorophenyloxycarbonyl group,
 2,6-dimethylphenyloxycarbonyl group, 2,4,6-trimethylphenyloxycarbonyl
 group, 2-methoxyphenyloxycarbonyl group, 2-butoxyphenyloxycarbonyl group,
 3-cyanophenyloxycarbonyl group, 3-nitrophenyloxycarbonyl group,
 2,2-ethylhexylphenyloxycarbonyl group,
 3-(2-ethylhexyloxy)phenyloxycarbonyl group, 4-fluorophenyloxycarbonyl
 group, 4-chlorophenyloxycarbonyl group, 4-cyanophenyloxycarbonyl group,
 4-butoxyphenyloxycarbonyl group and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, an acyloxy group
 having 2 through 20 carbon atoms is preferable as the acyloxy group, and
 examples thereof include an acetyloxy group, propanoyloxy group,
 butanoyloxy group, pentanoyloxy group, trifluoromethylcarbonyloxy group,
 octanoyloxy group, decanoyloxy group, undecanoyloxy group, octadecanoyloxy
 group and the like.
 Of the substituents represented by R.sup.11 and R.sup.20, an alkoxy group
 having 1 through 30 carbon atoms is preferable as the alkoxy group, and
 examples thereof include a methoxy group, ethoxy group, propyloxy group,
 isopropyloxy group, butoxy group, isobutoxy group, sec-butoxy group,
 t-butoxy group, pentyloxy group, isopenty,loxy group, hexyloxy group,
 heptnloxy group, octyloxy group, 2-ethylhexyloxy group, decyloxy group,
 dodecyloxy group, octadecyloxy group, ethoxycarbonylmethyloxy group,
 2-ethylhexyloxycarbonylmethyloxy group, aminocarbonylmethyloxy group,
 N,N-dibutylaminocarbonylmethyloxy group, N-methylaminocarbonylmethyloxy
 group, N-ethylaminocarbonylmethyloxy group, N-octylaminocarbonylmethyloxy
 group, N-methyl-N-benzylaminocarbonylmethyloxy group, benzyloxy group,
 cyanomethyloxy group and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, an aryloxy group
 having 6 through 30 carbon atoms is preferable as the aryloxy group, and
 examples thereof include a phenyloxy group, 1-naphthyloxy group,
 2-naphthyloxy group, 2-chlorophenyloxy group, 2-methylphenyloxy group,
 2-methoxyphenyloxy group, 2-butoxyphenyloxy group, 3-chlorophenyloxy
 group, 3-trifluoromethlyphenyloxy group, 3-cyanophenyloxy group,
 3-(2-ethylhexyloxy)phenyloxy group, 3-nitrophenyloxy group,
 4-fluorophenyloxy group, 4-cyanophenyloxy group, 4-butoxyphenyloxy group,
 4-(2-ethylhexyloxy)phenyloxy group, 4-octadecylphenyloxy group and the
 like.
 Of the substituents represented by R.sup.19 and R.sup.20, an alkylthio
 group having 1 through 30 carbon atoms is preferable as the alkylthio
 group, and examples thereof include a methylthio group, ethylthio group,
 propylthio group, isopropylthio group, butylthio group, isobutylthio
 group, sec-butyl thio group, t-butylthio group, pentylthio group,
 isopentylthio group, hexylthio group, heptylthio group, octylthio group,
 2-ethylhexylthio group, decylthio group, dodecylthio group, octadecylthio
 group, ethox ycarbonylmethio group, 2-ethyilhexyloxycarbonylmethylthio
 gcroup, aminocarbonylmethylthio group,
 N,N-dibutylamimiocarboonylmethylthlio group,
 N-methylaminocarbonylmethylthio group, N-ethylaminocarbonylmethylthio
 group, N-octylaminocarbonylmethylthio group,
 N-methyl-N-benzylaminocarbonylmethylthio group, benzylthio group,
 cyanomethylthio group and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, an arylthio group
 having 6 through 30 carbon atoms is preferable as the arylthio group, and
 examples thereof include a phenylthio group, 1-naphthylthio group,
 2-naphthylthio group, 2-chlorophenylthio group, 2-methylphenylthio group,
 2-methoxyphenylthio group, 2-butoxyphenylthio group, 3-chlorophenylthio
 group, 3-trifluoromethlyphenylthio group, 3-cyanophenylthio group,
 3-(2-ethylhexyloxy)phenylthio group, 3-nitrophenylthio group,
 4-fluorophenylthio group, 4-cyanophenylthio group, 4-butoxyphenylthio
 group, 4-(2-ethylhexyloxy)phenylthio group, 4-octadecylphenylthio group
 and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, the substituted
 sulfamoyl group includes a sulfamoyl group, N-alkylsulfamoyl group,
 N-arylsulfamoyl group, N,N-dialkylsulfamoyl group, N,N-diarylsulfamoyl
 group, N-alkyl-N-arylsulfamoyl group and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, a substituted
 sulfamoyl group having 0 through 30 carbon atoms is preferable as the
 substituted sulfamoyl group, and examples thereof include an
 N-methylsulfamoyl group, N-ethylsulfamoyl group, N-propylsulfamoyl group,
 N-butylsulfamoyl group, N-hexylsulfamoyl group, N-cyclohexylsulfamoyl
 group, N-octylsulfamoyl group, N-2-ethylhexylsulfamoyrl group,
 N-decylsulfamoyl group, N-octadecylsulfamoyl group, N-phenylsulfamoyl
 group, N-2-methylphenylsulfamol group, N-2-chlorophenylsulfamoyl group,
 N-9-methoxyphenylsulfamoyl group, N-2-isopropoxyphenylsulfamoyl group,
 N-2-(2-ethylhexyloxy)phenylsulfamoyl group, N-3-chlorophenylsulfamoyl
 group, N-3-nitrophenylsulfamoyl group, N-3-cyanophenylsulfamoyl group,
 N-4-methoxysulfamoyl group, N-4-(2-ethylhexyloxy)phenylsulfamoyl group,
 N-4-cyanophenylsulfamoyl group, N-methyl-N-phenylsulfamoyl group,
 N,N-dimethylsulfamoyl group, N,N-dibutylsulfamoyl group,
 N,N-diphenylsulfamoyl group, N,N-di-(2-ethylhexyl)sulfamoyl group and the
 like.
 Of the substituents represented by R.sup.19 and R.sup.20, an alkylsulfonyl
 group having 1 through 20 carbon atoms is preferable as the alkylsulfonyl
 group, and examples thereof include a methylsulfonyl group, ethylsulfonyl
 group, propylsulfonyl group, isopropylsulfonyl group, butylsulfonyl group,
 hexylsulfonyl group, cyclohexylsulfonyl group, octylsulfonyl group,
 2-ethylhexylsulfonyl group, decanoylsulfonyl group, dodecanoylsulfonyl
 group, octadecanoylsulfonyl group, cyanomethylsulfonyl group and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, an arylsulfonyl
 group having 6 through 30 carbon atoms is preferable as the arylsulfonyl
 group, and examples thereof include a phenylsulfonyl group,
 1-naphthylsulfonyl group, 2-naphthylsulfonyl group, 2-chlorophenylsulfonyl
 group, 2-methylphenylsulfonyl group, 2-methoxyphenylsulfonyl group,
 2-butoxyphenylsulfonyl group, 3-chlorophenylsulfonyl group,
 3-trifluoromethylphenylsulfonyl group, 3-cyanophenylsulfonyl group,
 3-(2-ethylhexyloxy)phenylsulfonyl group, 3-nitrophenylsulfonyl group,
 4-fluorophenylsulfonyl group, 4-cyanophenylsulfonyl group,
 4-butoxyphenylsulfonyl group, 4-(2-ethylhexyloxy)phenylsulfonyl group,
 4-octadccylphenylsulfonyl group and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, an
 alkylphosphoryl group having 2 through 40 carbon atoms is preferable as
 the alkylphosphoryl group, and examples thereof include a methylphosphoryl
 group, ethylphosphoryl group, propylphosphoryl group, isopropylphosphoryl
 group, butylphosphoryl group, isobutylphosphoryl group,
 sec-butylphosphoryl group, t-butylphosphoryl group, pentylphosphoryl
 group, isopentylphosphoryl group, hexylphosphoryl group, heptylphosphoryl
 group, octylphosphoryl group, 2-ethylhexylphosphoryl group,
 decylphosphoryl group, dodecylphosphoryl group, octadecylphosphoryl group,
 ethoxycarbonylmethylphosphoryl group,
 2-ethylhexyloxycarbonylmethylphosphoryl group,
 aminocarbonylmethylphosphoryl group,
 N,N-dibutylaminocarbonylmethylphosphoryl group,
 N-methylaminocarbonylmethylphosphoryl group,
 N-ethylaminocarbonylmethylphosphoryl group,
 N-octylaminocarbonylmethylphosphoryl group, benzylphosphoryl group and the
 like.
 Of the substituents represented by R.sup.19 and R.sup.20, an arylphosphoryl
 group having 12 through 50 carbon atoms is preferable as the
 arylphosphoryl group, and examples thereof include a phenylphosphoryl
 group, 1-naphthylphosphoryl group, 2-naphthylphosphoryl group,
 2-chlorophenylphosphoryl group, 2-methylphenylphosphoryl group,
 2-methoxyphenylphosphoryl group, 2-butoxyphenylphosphoryl group,
 3-chlorophenylphosphoryl group, 3-trifluoromethylphenylphosphoryl group,
 3-cyanophenylphosphoryl group, 3-(2-ethylhexyloxy)phenylphosphoryl group,
 3-nitrophenylphosphoryl group, 4-fluorophenylphosphoryl group,
 4-cyanophenylphosphoryl group, 4-butoxyphenylphosphoryl group,
 4-(2-ethylhexyloxy)phenylphosphoryl group, 4-octadecylphenylphosphoryl
 group and the like.
 Of the substituents represented by R.sup.19 and R.sup.20, the substituted
 amino group includes an amino group, N-alk7lamino group, N-arylamino
 group, N-acylamino group, N-sulfonylamino group, N,N-dialkylamino group,
 N,N-diarylamino group, N-alkyl-N-arylamino group, N,N-disulfonylamino
 group and the like.
 As the substituted amino group, a substituted amino group having 0 through
 50 carbon atoms is preferable, and examples thereof include an
 N-methylamino group, N-ethylamino group, N-propylamino group,
 N-isopropylamino group, N-tert-butylamino group, N-hexylamino group,
 N-cyclohexylamino group, N-octylamino group, N-2-ethylhexylamino group,
 N-decylamino group, N-octadecylamino group, N-benzylamino group,
 N-phenylamino group, N-2-methylphenylamino group, N-2-chlorophenylamino
 group, N-2-methoxyphenylamino group, N-2-isopropoxyphenylamino group,
 N-2-(2-ethylhexyloxy)phenylamino group, N-3-chlorophenylamino group,
 N-3-nitrophenylamino group, N-3-cyanophenylamino group, N-4-methoxyamino
 group, N-4-(2-ethylhexyloxy)phenylamino group, N-4-cyanophenylamino group,
 N-methyl-N-phenylamino group, N,N-dimethylamino group, N,N-dibutylamino
 group, N,N-diphenylamino group, N,N-diacetylamino group,
 N,N-dibenzoylamino group, N,N-(dibutylcarbonyl)amino group,
 N,N-(di-2-ethylhexyl1carbonyl)amino group, N,N-(dimethylsulfonyl)amino
 group, N,N-(diethylsulfonyl)amino group, N,N-(dibutylsulfonyl)amino group,
 N,N-(2-ethylhexylsulfonyl)amino group, N,N-(diphenylsulfonyl)amino group
 and the like.
 Of the substituents represented by R.sup.30 and R.sup.40, an alkyl group,
 aryl group and acyl group may have the same contents as those of the alkyl
 group, aryl group and acyl group explained above for R.sup.19 and
 R.sup.20. Further, of the substituents represented by R.sup.30 and
 R.sup.40, a cycloalkyl group having 3 through 12 carbon atoms, which may
 have further more substituents, is preferable as the cycloalkyl group, and
 examples thereof include a substituted or unsubstituted cyclopentane,
 cyclohexane, cycloheptane and the like. Likewise, of the substituents
 represented by R.sup.30 and R.sup.40, a piperidyl group includes the ones
 expressed by the following formulae.
 ##STR175##
 In the above formula, R.sup.100 represents an alkyl group having 1 through
 4 carbon atoms.
 Of the substituents represented by R.sup.30 and R.sup.40, R.sup.50 through
 R.sup.80 of the substituents expressed by --C.sub.n H.sub.2n
 N(R.sup.50)(R.sup.60) or --C.sub.m H.sub.2m XC.sub.1 H.sub.21
 N(R.sup.70)(R.sup.80) represents a hydrogen atom, alkyl group or an aryl
 group that may have substituents. As the alkyl group, an alkyl group
 having 1 through 8 carbon atoms is preferable, and as the aryl group, a
 phenyl group is preferable. In the formula, X represents an oxygen atom,
 sulfur atom, or N(R.sup.90). R.sup.90 represents a hydrogen atom, an alkyl
 group or an aryl group that may have substituents, and of the above
 substituents, an alkyl group having 1 through 4 carbon atoms, and a phenyl
 group are preferable. Further, in the formula, m, n and 1 represent
 integers from 1 through 12, and 2 through 4 are preferable. Likewise, the
 combined group represented by C.sub.n H.sub.2n, C.sub.m H.sub.2m and
 C.sub.1 H.sub.21 in the two formulae may be linear or branched, and
 examples of the structure thereof include the following formulae.
 ##STR176##
 Further, rings that can be formed by R.sup.30 and R.sup.40, or R.sup.50 and
 R.sup.60, or R.sup.70 and R.sup.80, or R.sup.70 and R.sup.90, or R.sup.80
 and R.sup.90 include the following rings and the like.
 ##STR177##
 In the above formulae, R.sup.110 through R.sup.130 each independently
 represents a hydrogen atom, an alkyl group, aryl group or acyl group. Of
 the above, an alkl group having 1 through 4 carbon atoms is preferable.
 Next, a description will given of a synthesizing method of the
 pyrrolo[1,2-a]pyrimidine compound represented by the general formula (3).
 The pyrrolo[1,2-a]pyrimidine compound represented by the general formula
 (3) can be synthesized, for example, by following the formula given below.
 ##STR178##
 R.sup.19, R.sup.20, R.sup.30 and R.sup.40 in the reaction formula have the
 same meanings as those in the general formula (3), respectively.
 The pyrrolo[1,2-a]pyrimidine compound represented by the above general
 formula (3) can be obtained by first reacting the compound (A) (the amino
 structure) with chlorosulfonylisocyanate, to which HN(R.sup.30)(R.sup.40)
 is added thereafter for causing a reaction.
 In the reactions represented by the above scheme, at the first stage for an
 addition reaction with chlorosulfonylisocyanate, the amount of
 chlorosulfonylisocyanate used is 0.9 through 2.5 equivalent and preferably
 1.1 through 1.6 equivalent in relation to the compound (A) used as raw
 material.
 As the solvent for use in the reaction, various types of solvents that are
 inert to chlorosulfonylisocyanate and a mixture thereof can be used,
 examples of the solvents including aromatic hydrocarbons such as benzene,
 toluene and xylene, chain or cyclic aliphatic hydrocarbons such as
 pentane, hexane, heptane and cyclohexane, ethers such as diethyl ether,
 dilsopropyl ether, tetrahydrofuran and ethyleneglycoldimethylether,
 halogenated hydrocarbons such as dichloromethane, chloroform,
 1,2-dichloroethane, nitrites such as acetonitrile and the like. Of the
 above solvents, acetonitrile and tetrahydrofuran are preferable. The
 amount to be used of the above solvents is not particularly limited.
 Examples of a method for running the reaction include a method in which
 chlorosulfonylisocyanatc is dripped into a solution of (A).
 The temperature at which the reaction is run is approximately from -40
 through 40.degree. C., and is preferably from -15 through 25.degree. C.
 The time of the reaction is normally approximately from 0.5 through 24
 hours, which varies depending on the temperature of the reaction.
 Subsequently, the second stage, i.e., the reaction with
 HN(R.sup.30)(R.sup.40), can be carried out without treating the addition
 reaction liquid of chlorosulfonylisocyanate.
 The amount of HN(R.sup.30)(R.sup.40) to be used is 1.8 through 4.0
 equivalent, and is preferably 1.8 through 3.0 equivalent, in relation to
 the compound (A) used as raw material.
 The temperature at which the reaction in the second stage is run is
 approximately from -40 through 40.degree. C., and is preferably from -25
 through 40.degree. C. The time of the reaction at the second stage is
 normally from 0.5 through 24 hours, which varies depending on the reaction
 temperature.
 The compound (A) used as raw material can be synthesized by a method
 described in Japanese Patent Application No. 10-210029.
 Here, specific examples of the pyrrolo[1,2-a]pyrimidine compound
 represented by the general formula (3) are given. However, the
 pyrrolo[1,2-a]pyrimidine compound of the present invention is not limited
 to the following examples. The following are examples of substituents
 represented by R.sup.19, R.sup.20, R.sup.30 and R.sup.40 in the general
 formula (3). Further, specific examples of compounds in which the above
 substituents are combined are shown in Tables 8 through 16.
 ##STR179##
 ##STR180##
 ##STR181##
 Examples of rings that are formed by R.sup.30 and R.sup.40, or R.sup.50 and
 R.sup.60, or R.sup.70 and R.sup.80, or R.sup.70 and R.sup.90, or R.sup.80
 and R.sup.90 include the following rings.
 ##STR182##
 TABLE 8
 Coupler
 No. R.sup.19 R.sup.20 R.sup.30 R.sup.40
 (1) ##STR183## --CN --H ##STR184##
 (2) ##STR185## --CN --H ##STR186##
 (3) ##STR187## --CN --H ##STR188##
 (4) ##STR189## --CN --CH.sub.3 ##STR190##
 (5) ##STR191## --CN --C.sub.2 H.sub.5 ##STR192##
 (6) ##STR193## --CN --C.sub.6 H.sub.13 ##STR194##
 (7) ##STR195## --CN --C.sub.2 H.sub.5 ##STR196##
 (8) ##STR197## --CN --C.sub.4 H.sub.9 ##STR198##
 (9) ##STR199## --CN ##STR200##
 (10) --CH.sub.3 --CN ##STR201##
 TABLE 9
 Coupler
 No. R.sup.19 R.sup.20 R.sup.30 R.sup.40
 (11) --H --CN --C.sub.6 H.sub.13 ##STR202##
 (12) --CH.sub.3 --CN --H ##STR203##
 (13) --CH.sub.3 --CN --C.sub.2 H.sub.5 ##STR204##
 (14) --CH.sub.3 --CN --H ##STR205##
 (15) --CH.sub.3 --CN ##STR206##
 (16) ##STR207## --CN --H ##STR208##
 (17) ##STR209## --CN --CH.sub.3 ##STR210##
 (18) ##STR211## --CN --C.sub.2 H.sub.5 ##STR212##
 (19) --CN --CN --C.sub.4 H.sub.9 ##STR213##
 (20) ##STR214## --CN ##STR215##
 TABLE 10
 Coupler
 No. R.sup.19 R.sup.20 R.sup.30 R.sup.40
 (21) ##STR216## --CN ##STR217## ##STR218##
 (22) ##STR219## --CN --CH.sub.3 ##STR220##
 (23) ##STR221## --CN --C.sub.4 H.sub.9
 ##STR222##
 (24) ##STR223## --CN --C.sub.4 H.sub.9 --C.sub.4
 H.sub.9
 (25) ##STR224## --CN --CH.sub.3 ##STR225##
 (26) ##STR226## --CN --C.sub.6 H.sub.13 --C.sub.6
 H.sub.13
 (27) ##STR227## --CN --H ##STR228##
 (28) ##STR229## --CN --H --(CH.sub.2).sub.3
 OC.sub.12 H.sub.25
 (29) ##STR230## --CN --H ##STR231##
 (30) ##STR232## --CN --H ##STR233##
 TABLE 11
 Coupler
 No. R.sup.19 R.sup.20 R.sup.30
 R.sup.40
 (31) ##STR234## ##STR235## --H
 ##STR236##
 (32) ##STR237## ##STR238## --H
 ##STR239##
 (33) ##STR240## ##STR241## --H
 ##STR242##
 (34) ##STR243## ##STR244## --CH.sub.3
 ##STR245##
 (35) ##STR246## ##STR247## --C.sub.2 H.sub.5
 ##STR248##
 (36) ##STR249## ##STR250## --CH.sub.3
 ##STR251##
 (37) ##STR252## ##STR253## --C.sub.2 H.sub.5
 ##STR254##
 (38) ##STR255## ##STR256## --H
 ##STR257##
 (39) ##STR258## --SO.sub.2 CH.sub.3 --H
 ##STR259##
 (40) ##STR260## ##STR261## --CH.sub.3
 ##STR262##
 TABLE 12
 Coupler
 No. R.sup.19 R.sup.20 R.sup.30
 R.sup.40
 (41) ##STR263## ##STR264##
 ##STR265##
 (42) ##STR266## ##STR267##
 ##STR268##
 (43) ##STR269## ##STR270## ##STR271##
 ##STR272##
 (44) ##STR273## ##STR274## --H
 ##STR275##
 (45) ##STR276## ##STR277## --CH.sub.3
 --CH.sub.3
 (46) ##STR278## ##STR279## --CH.sub.3
 ##STR280##
 (47) ##STR281## ##STR282## --H
 ##STR283##
 (48) ##STR284## ##STR285## --C.sub.6 H.sub.13
 --C.sub.6 H.sub.13
 (49) ##STR286## ##STR287##
 ##STR288##
 (50) ##STR289## ##STR290## --H
 ##STR291##
 TABLE 13
 Coupler
 No. R.sup.19 R.sup.20 R.sup.30
 R.sup.40
 (51) ##STR292## ##STR293## --H
 ##STR294##
 (52) ##STR295## ##STR296## --H
 ##STR297##
 (53) ##STR298## ##STR299## --H
 ##STR300##
 (54) ##STR301## ##STR302## --CH.sub.3
 ##STR303##
 (55) ##STR304## ##STR305## --C.sub.2 H.sub.5
 ##STR306##
 (56) ##STR307## --CO.sub.2 C.sub.2 H.sub.5 --H
 ##STR308##
 (57) ##STR309## --CO.sub.2 C.sub.2 H.sub.5 --H
 ##STR310##
 (58) ##STR311## ##STR312## --CH.sub.3
 ##STR313##
 (59) ##STR314## ##STR315## --C.sub.2 H.sub.5
 ##STR316##
 (60) ##STR317## ##STR318## ##STR319##
 TABLE 14
 Coupler
 No. R.sup.19 R.sup.20 R.sup.30
 R.sup.40
 (61) ##STR320## ##STR321##
 ##STR322##
 (62) ##STR323## --CO.sub.2 C.sub.2 H.sub.5
 ##STR324##
 (63) ##STR325## --CO.sub.2 C.sub.2 H.sub.5 --CH.sub.3
 ##STR326##
 (64) ##STR327## --CO.sub.2 C.sub.2 H.sub.5 --H
 ##STR328##
 (65) ##STR329## --CO.sub.2 C.sub.2 H.sub.5 --H
 ##STR330##
 (66) ##STR331## ##STR332## --CH.sub.3
 ##STR333##
 (67) ##STR334## ##STR335## --H
 ##STR336##
 (68) ##STR337## --CO.sub.2 C.sub.2 H.sub.5 --CH.sub.3
 ##STR338##
 (69) ##STR339## --CO.sub.2 C.sub.2 H.sub.5 --H
 ##STR340##
 (70) ##STR341## ##STR342## --H
 ##STR343##
 TABLE 15
 Coupler
 No. R.sup.19 R.sup.20 R.sup.30
 R.sup.40
 (71) ##STR344## ##STR345## --CH.sub.3
 ##STR346##
 (72) ##STR347## ##STR348##
 ##STR349##
 (73) ##STR350## ##STR351##
 ##STR352##
 (74) ##STR353## --CO.sub.2 C.sub.2 H.sub.5 ##STR354##
 ##STR355##
 (75) ##STR356## --CO.sub.2 C.sub.2 H.sub.5 --H
 ##STR357##
 (76) ##STR358## --CO.sub.2 C.sub.2 H.sub.5 --CH.sub.3
 ##STR359##
 (77) ##STR360## ##STR361## --CH.sub.3
 ##STR362##
 (78) ##STR363## ##STR364## --H
 ##STR365##
 (79) ##STR366## --CONHC.sub.8 H.sub.17 --CH.sub.3
 ##STR367##
 (80) ##STR368## --CONHC.sub.8 H.sub.17 --C.sub.2 H.sub.5
 ##STR369##
 TABLE 16
 Coupler
 No. R.sup.19 R.sup.20 R.sup.30 R.sup.40
 (81) ##STR370## ##STR371## ##STR372##
 (82) ##STR373## ##STR374## ##STR375##
 (83) ##STR376## --CONHC.sub.8 H.sub.17 --CH.sub.3
 ##STR377##
 (84) ##STR378## --CONHC.sub.8 H.sub.17 --H ##STR379##
 (85) ##STR380## --CONHC.sub.8 H.sub.17 --C.sub.4 H.sub.9
 --C.sub.4 H.sub.9
 (86) ##STR381## ##STR382## ##STR383##
 Next, the heat-sensitive recording material of the present invention will
 be described in detail.
 The heat-sensitive recording material of the present invention comprises a
 substrate on which a heat-sensitive recording layer is provided. Further,
 the heat-sensitive recording material may include other layers if needed.
 Heat-sensitive Recording Layer
 The heat-sensitive recording layer contains a coupler and a diazonium salt
 compound, and if necessary, may contain other components.
 Coupler
 The coupler contained in the heat-sensitive recording layer uses at least
 one type of the pyrrolo[1,2-a]pyrimidine compound selected from the
 pyrrolo[1,2-a]pyrimidine compound represented by the general formula (1),
 the pyrrolo[1,2-a]pyrimidine compound represented by the general formula
 (2) and the pyrrolo[1,2-a]pyrimidine compound represented by the general
 formula (3). A single pyrrolo[1,2-a]pyrimidine compound or two or more
 types of the above compounds may be used.
 The coupler described above participates in a coupling reaction with a
 diazo compound in a basic atmosphere and/or neutral atmosphere to form a
 dye. The coupler in the present invention can be used together with known
 couplers, in accordance with various objects such as hue control and the
 like.
 Examples of the known couplers include a so-called active meth,Ilne
 compound having a methylene group adjacent to a carbonyl group, a phenol
 derivative, a naphthol derivative and the like. Specific examples thereof
 preferably include the following compounds, which are used in a range
 corresponding to the objects of the present invention. Preferable examples
 include resorcin, phloroglucin, 2,3-dihydroxynaphthalene, sodium
 2,3-dihydroxynaphthalene-6-sulfonate, 1-hydroxy-2-naphthoic
 morpholinopropylamide, sodium 2-hydroxy-3-naphthalenesulfonate,
 2-hydroxy-3-naphthalenesulfonic anilide, 2-hydroxy-3-naphthalenesulfonic
 morpholinopropylamide,
 2-hydroxy-3-naphthalenesulfonic-2-ethylhexyloxypropylamide,
 2-hydroxy-3-naphthalenesulfonic-2-ethylhexylamide, 5-acetamide-1-naphthol,
 sodium 1-hydroxy-8-acetamidenaphthalene-3,6-disulfonate,
 1-hydroxy-8-acetamidenaphthalene-3,6-disulfonic dianilide,
 1,5-dihydroxynaphthalene, 2-hydroxy-3-naphthoic morpholinopropylamide,
 2-hydroxy-3-naphthoic octylamide, 2-hydroxy-3-naphthoic anilide,
 5,5-dimethyl-1,3-cyclohexanedione, 1,3-cyclopentanedione,
 5-(2-n-tetradecyloxyphenyl)-1,3-cyclohexanedione,
 5-phenyl-4-methoxycarbonyl-1,3-cyclohexanedione,
 5-(2,5-di-n-octyloxyphenyl)-1,3-cyclohexanedione,
 N,N'-dicyclohexylbarbituric acid, N,N'-di-n-dodecylbarbituric acid,
 N-n-octyl-N'-n-octadecylbarbituric acid, N-phenyl-N'-(2,5-di-n-oct3,
 loxyphenyl)barbituric acid, N,N'-bis(octadecyloxycarbonylmethyl)barbituric
 acid, 1-phenyl-3-methyl-5-pyrazolone,
 1-(2,4,6-trichlorophenyl)-3-anilino-5-pyrazolone,
 1-(2,4,6-trichlorophenyl)-3-benzamide-5-pyrazolone,
 6-hydroxy-4-methyl-3-cyano-1-(2-ethylhexyl)-2-pyridone,
 2,4-bis-(benzoylacetamide)toluene,
 1,3-bis-(pivaloylacetamidemethyl)benzene, benzoylacetonitrile,
 thenoylacetonitrile, acetacetanilide, benzoylacetanilide,
 pivaloylacetanilide,
 2-chloro-5-(N-n-butylsulfamoyl)-1-pivaloylacctamidebeizeie,
 1-(2-ethylhexyloxypropyl)-3-cyaho-4-methyl-6-hydlroxy-1,2-dihydropyridine-
 2-one,
 1-(dodecyloxypropyl)-3-acetyl-4-methyl-6-hydroxy-1,2-dihydropyridine-2-one
 , 1-(4-n-octyloxyphenyl)-3-tert-butyl-5-aminopyrazole and the like.
 Details of the couplers are described in Japanese Patent Application
 Laid-Open (JP-A) Nos. 4-201483, 7-223367, 7-223368, 7-323660, Japanese
 Patent Application Nos. 5-278608, 5-297024, 6-18669, 6-18670, 7-316280,
 8-027095, 8-027096, 8-030799, 8-12610, 8-132394, 8-358755, 8-358756,
 9-069990 and the like.
 The amount of the coupler added in the heat-sensitive recording layer is
 approximately from 0.02 through 5 g/m.sup.2 of the heat-sensitive
 recording layer, and preferably from 0.1 through 4 g/m.sup.2 in view of
 the effects.
 An amount added of less than 0.02 g/m.sup.2 is not preferable from the
 standpoint of the color forming property, and an amount added of over 5
 g/m.sup.2 is not preferable from the standpoint of suitability for
 coating.
 A water-soluble polymer may be added to the coupler used in the present
 invention together with other components after which the result is
 dispersed in a solid state by a sand mill or the like and used. Further,
 the coupler may be used, together with a suitable emulsification
 assistant, as an emulsifier.
 The solid state dispersing method and emulsifying method are not
 particularly limited, and conventionally known methods can be used.
 Details of the above methods are described in Japanese Patent Application
 Laid-Open (JP-A) Nos. 59-190886, 2-141279 and 7-17145.
 Diazonium Salt Compound
 The diazonium salt compound used in the present inventior is a compound
 represernted by the following general formula:
 Ar--N.sub.2.sup.+ X.sup.-
 (wherein, in the formula, Ar represents an aromatic moiety, and X.sup.-
 represents an acid anion). Further, the diazonium salt compound is a
 compound that undergoes a coupling reaction with the coupler with heating
 so as to form color, and is decomposed by light. The maximum absorption
 wavelength thereof can be controlled by the position and type of the
 substituent on the Ar moiety.
 Specific examples of the diazonium forming a salt include
 4-(p-tolylthio)-2,5-dibutoxybenzenediazonium,
 4-(4-chlorophenylthio)-2,5-dibutoxybenzenediazonium, 4-(N,N-dimethylamino)
 benzenediazonium, 4-(N,N-diethylamino)benzenediazonium,
 4-(N,N-dipropylamino)benzenediazonium,
 4-(N-methyl-N-benzylamino)benzenediazonium,
 4-(N,N-dibenzylamino)benzenediazonium,
 4-(N-ethyl-N-hydroxyethylamino)benzenediazonium,
 4-(N,N-diethylamino)-3-methoxybenzenediazonium,
 4-(N,N-dimethylamino)-2-methoxybenzenediazonium,
 4-(N-benzoylamino)-2,5-diethoxybenzenediazonium,
 4-morpholino-2,5-dibutoxybenzenediazonium, 4-anilinobenzenediazonium,
 4-[N-(4-methoxybenzoyl)amino]-2,5-diethoxybenzenediazonium,
 4-pyrrolidino-3-ethylbenzenediazonium,
 4-[N-(1-methyl-2-(4-methoxyphenoxy)ethyl)-N-hexylamino]-2-hexyloxybenzened
 iazonium,
 4-[N-(2-(4-methoxyphenoxy)ethyl)-N-hexylamino]-2-hexyloxybenzenediazonium,
 2-(1-ethylpropyloxy)-4-[di-(di-n-butylaminocarbonylmethyl)amino]benzenedia
 zonium,
 2-benzylsulfonyl-4-[N-methyl-N-(2-octanoyloxyethyl)]aminobenzenediazonium
 and the like.
 The maximum absor ption wavelength .lambda..sub.max of the diazonium salt
 compound used in the present invention is preferably 450 nm or less from
 the standpoint of effects, and further preferably from 290 through 440 nm.
 Diazonium salt compounds having a .lambda..sub.max higher than the above
 wavelength range are not preferable from the standpoint of storability
 before processing. Diazonium salt compounds having a .lambda..sub.max
 lower than the above wavelength range are not preferable from the
 standpoint of image fixing, property, image storability, and hue of the
 formed cyan color when the diazonium salt compound is used in combination
 with a coupler.
 The diazonium salt compound used in the present invention preferably has 12
 or more carbon atoms, solubility in water of 1% or less, and solubility in
 ethyl acetate of 5% or more.
 Among the above diazonium salt compounds, it is further preferable to use
 diazonium salt compounds represented by the general formulae (4) through
 (6) from the standpoint of hues of the dyes, image storability and image
 fixing property.
 In the general formula (4), Ar represent s a substituted or unsubstituted
 aryl group.
 Examples of the substituent thereof include an alkyl group, alkoxy group,
 alklithio group, aryl group, arylox group, arylthio group, acyl group,
 alkoxecarbonyl group, carbamoyl group, carboamide group, sulfonli broup,
 sulfamoyl group, sulfonamide group, ureide group, halogen group, amino
 group, heterocyclic group and the like. The substituents described above
 may further be substituted.
 As the aryl group represented by the Ar, an aryl group hivin 6 throumh 30
 carbon atoms is preferable, and examples thereof include, but are not
 particularly limited to, a phenyl group, 2-methylphenyl group,
 2-chlorophenyl group, 2-methoxyphenyl group, 2-butoxyphenyl group,
 2-(2-ethylhexyloxy)phenyl group, 2-octyloxyphenyl group,
 3-(2,4-di-t-pentylphenoxyethoxy)phenyl group, 4-chlorophenyl group,
 2,5-dichlorophenyl group, 2,4,6-trimethylphenyl group, 3-chlorophenyl
 group, 3-methylphenyl group, 3-methoxyphenyl group, 3-butoxyphenyl group,
 3-cyanophenyl group, 3-(2-ethylhexyloxy)phenyl group, 3,4-dichlorophenyl
 group, 3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group,
 3-(dibutylaminocarbonylmethoxy)phenyl group, 4-cyanophenyl group,
 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxyphenyl group,
 4-(2-ethylhexyloxy)phenyl group, 4-benzylphenyl group,
 4-aminosulfonylphenyl group, 4-N,N-dibutylaminosulfonylphenyl group,
 4-ethoxycarbonylphenyl group, 4-(2-ethylhexylcarbonyl)phenyl group,
 4-fluorophenyl group, 3-acetylphenyl group, 2-acetylaminophenyl group,
 4-(4-chlorophenylthio)phenyl group,
 4-(4-methylphenyl)thio-2,5-butoxyphenyl group,
 4-(N-benzyl-N-methylamino)-2-dodecyloxycarbonylphenyl group and the like.
 Likewise, the above groups may further be substituted by an alkyloxy
 group, alkylthio group, substituted phenyl group, cyano group, substituted
 amino group, halogen atom, heterocyclic group or the like.
 R.sup.11 and R.sup.12 each independently represents a substituted or
 unsubstituted alkyl group, or a substituted or unsubstituted aryl group.
 R.sup.11 and R.sup.12 may be the same or different from each other.
 Examples of the substituent thereof include, but are not limited to, an
 alkoxy group, alkoxycarbonyl group, alkylsulfonyl group, substituted amino
 group, substituted amide group, aryl group, aryloxy group and the like.
 When R.sup.11 and R.sup.12 each independently represents an alkyl group, an
 alkyl group having 1 through 18 carbon atoms is preferable as the alkyl
 group, and examples thereof include a methyl group, trifluoromethyl group,
 ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group,
 t-butyl group, pentyl group, isopentyl group, cyropentyl group, hexyl
 group, cyclohexyl group, octyl group, t-octyl group, 2-ethylhexyl group,
 nonyl group, octadecyl group, benzyl group, 4-methoxybenzyl group,
 triphenylmethyl group, ethoxycarbonylmethyl group, butoxycarbonylmethyl
 group, 2-ethylhexyloxycarbonylmethyl group,
 2',4'-diisopentylphenyloxymethyl group, 2',4'-di-t-butylphenyloxymethyl
 group, dibenzylaminocarbonylmethyl group, 2,4-di-t-amylphenyloxypropyl
 group, ethoxycarbonyapropyl group, 1-(2',4-di-t-amylphenyloxy)propyl
 group, acetylaminoethyl group, 2-(N,N-dimethylamino)ethyl group,
 2-(N,N-diethylamino)propyl group, methanesulfonylaminopropyl group,
 acetylaminoethyl group , 2-(N,N-dimethylamino)ethyl group,
 2-(N,N-diethylamino)propyl group and the like.
 When R.sup.11 and R.sup.12 each independently represents an aryl group, an
 aryl group having 6 through 30 carbon atoms is preferable as the aryl
 group, and examples thereof include, but are not particularly limited to,
 a phenyl group, 2-methylphenyl roup, 2-chliorophenyl group,
 2-methoxyphenyl group, 2-butoxyphenyl group, 2-(2-ethylhexyloxy)phenyl
 group, 2-octoxyphenyl group, 3-(2,4-di-t-pentylphenoxyethoxy)phenyl group,
 4-chlorophenyl group, 2, '-dichlorophenyl group, 2,4,6-trimethylamienol
 group, 3-chlorophenyl group, 3-methylphenyl group, 3-methoxyphenyl group,
 3-butoxuphenyl group, 3-cyanophenyl group, 3-(2-ethylhexylox,)phenyl
 group, 3,4-dichlorophenyl group, 3,5-dichlorophenyl group,
 3,4-dimethoxyphenyl group, 3-(dibutylaminocarbonylmethoxy)phenyl group,
 4-cyanophenyl group, 4-methylphenyl group, 4-methoxyphenyl group,
 4-butoxyphenyl group, 4-(2-ethylhexyloxy)phenyl group, 4-benzylphenyl
 group, 4-aminosulfonylphenyl group, 4-N,N-dibutylaminosulfonylphenyl
 group, 4-ethoxycarbonylphenyl group, 4-(2-ethylhexylcarbonyl)phenyl group,
 4-fluorophenyl group, 3-acetylphenyl group, 2-acetylaminophenyl group,
 4-(4-chlorophenylthio)phenyl group,
 4-(4-methylphenyl)thio-2,5-butoxyphenyl group,
 4-(N-benzyl-N-methylamino)-2-dodecyloxycarbonylphenyl group and the like.
 Likewise, the above groups may further be substituted by an alkyloxy
 group, alkylthio group, substituted phenyl group, cyano group, substituted
 amino group, halogen atom, heterocyclic group or the like.
 In the general formula (5), R.sup.14, R.sup.15 and R.sup.16 each
 independently represents a substituted or unsubstituted alkyl group, or a
 substituted or unsubstituted aryl group. R.sup.14, R.sup.15 and R.sup.16
 may be the same or different from each other.
 Examples of the substituent thereof include an alkyl group, alkoxy group,
 alkylthio group, aryl group, aryloxy group, arylthio group, acyl group,
 alkoxycarbonyl group, carbamoyl group, carboamide group, sulfonyl group,
 sulfamoyl group, sulfonamide group, ureide group, halogen atom, amino
 group, heterocyclic group and the like.
 When R.sup.14, R.sup.15 and R.sup.16 each independently represents an alkyl
 group, an alkyl group having 1 through 18 carbon atoms is preferable as
 the alkyl group, and examples thereof include a methyl group,
 trifluoromethyl group, ethyl group, propyl group, isopropyl group, butyl
 group, sec-butyl group, t-butyl group, pentyl group, isopentyl group,
 cyclopentyl group, hexed group, cyclohexyl group, octal group, t-octyl
 group, 2-ethylhexyl group, nonyl group, octadecyl group, benzyl group,
 4-methoxybenzyl group, triphenylmethyl group, ethoxycarbonylmethyl group,
 butoxycarbonylmethyl group, 2-ethylhexyloxycarbonylmethyl group,
 2',4'-diisopentylphenyloxymethyl group, 2',4'-di-t-butylphenyloxymethyl
 group, dibenzylaminocarbonylmethyl group, 2,4-di-t-amylphenyloxypropyl
 group, ethoxycarbonylpropyl group, 1-(2',4'-di-t-amylphenyloxy)propyl
 group, 2-(N,N-dimethylamino)ethyl group, 2-(N,N-diethylamino)propyl group,
 methanesulfonylaminopropyl group, acetylaminoethyl group,
 2-(N,N-dimethylamino)ethyl group, 2-(N,N-diethylamino)propyl group,
 1-methyl-2-(4-methoxyphenoxy)ethyl group, di-n-butylaminocarbonylmethyl
 group, di-n-octylaminocarbonylmethyl group and the like.
 When R.sup.14, R.sup.15 and R.sup.16 each independently represents an aryl
 group, an aryl group having 6 through 30 carbon atoms is preferable as the
 aryl group, and examples thereof include, but are not particularly limited
 to, a phenyl group, 2-methylphenyl group, 2-chlorophenyl group,
 2-methoxyphenyl group, 2-butoxyphenyl group, 2-(2-ethylhexyloxy)phenyl
 group, 2-octyloxyphenyl group, 3-(2,4-di-t-pentylphenoxyethoxy)phenyl
 group, 4-chlorophenyl group, 2,5-dichlorophenyl group,
 2,4,6-trimethylphenyl group, 3-chlorophenyl group, 3-methylphenyl group,
 3-methoxyphenyl group, 3-butoxyphenyl group, 3-cyanophenyl group,
 3-(2-ethylhexyloxy)phenyl group, 3,4-dichlorophenyl group,
 3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group,
 3-(dibutylaminocarbonylmethoxy)phenyl group, 4-cyanophenyl group,
 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxyphenyl group,
 4-(2-ethylhexyloxy)phenyl group, 4-benzylphenyl group,
 4-aminosulfonylphenyl group, 4-N,N-dibutylaminosulfonylphenyl group,
 4-ethoxycarbonylphenyl group, 4-(2-ethylhexylcarbonyl)phenyl group,
 4-fluorophenyl group, 3-acetylphenyl group, 2-acetylaminophenyl group,
 4-(4-chlorophenylthio)phenyl group,
 4-(4-methylphenyl)thio-2,5-butoxyphenyl group,
 4-(N-benzyl-N-methylamino)-2-dodecyloxycarbonylphenyl group and the like.
 Likewise, the above groups may further be substituted by an alkyloxy
 group, alkylthio group, substituted phenyl group, cyano group, substituted
 amino group, halogen atom, heterocyclic group or the like.
 In the general formula (7), Y represents a hydrogen atom or an --OR.sup.13
 group. In the --OR.sup.13 group, R.sup.13 represents a substituted or
 unsubstituted alkyl group, or a substituted or unsubstituted aryl group.
 Examples of the substituent thereof include an alkyl group, alkoxy group,
 alkylthio group, aryl group, aryloxy group, arylthio group, acyl group,
 alkoxycarbonyl group, carbamoyl group, carboamide group, sulfonyl group,
 sulfamoyl group, sulfonamide group, ureide group, halogen atom, amino
 group, heterocyclic group and the like. From the standpoint of control of
 hue, Y preferably represents a hydrogen atom or an alkoxy group in which
 R.sup.13 is an alkyl group.
 When R.sup.13 in the --OR.sup.13 group represents an alkyl group, an alkyl
 group having 1 through 18 carbon atoms is preferable as the alkyl group,
 and examples thereof include a methyl group, trifluoromethyl group, ethyl
 group, propyl group, isopropyl group, butyl group, sec-butyl group,
 t-butyl group, pentyl group, isopentyl group, cyclopentyl group, hexyl
 group, cyclohexyl group, octyl group, t-octyl group, 2-ethylhexyl group,
 nonyl group, octadecyl group, benzyl group, 4-methoxybenzyl group,
 triphenylmethyl group, ethoxycarbonylmethyl group, butoxycarbonylmethyl
 group, 2-ethylhexyloxycarbonylmethyl group,
 2',4'-diisopentylphenyloxymethyl group, 2',4'-di-t-butylphenyloxymethyl
 group, dibenzylaminocarbonylmethyl group, 2,4-di-t-amylphenyloxypropyl
 group, ethoxycarbonylpropyl group, 1-(2',4'-di-t-amylphenyloxy)propyl
 group, acetylaminoethyl group, 2-(N,N-dimethylamino)ethyl group,
 2-(N,N-diethylamino)propyl group, methanesulfonylaminopropyl group,
 acetylaminoethyl group, 2-(N,N-dimethylamino)ethyl group,
 2-(N,N-diethylamino)propyl group and the like.
 When R.sup.13 in the --OR.sup.13 group represents an aryl group, an aryl
 group having 6 through 30 carbon atoms is preferable as the aryl group,
 and examples thereof include, but are not particularly limited to, a
 phenyl group, 2-methylphenyl group, 2-chlorophenyl group, 2-methoxyphenyl
 group, 2-butoxyphenyl group, 2-(2-ethylhexyloxy)phenyl group,
 2-octyloxyphenyl group, 3-(2,4-di-t-pentyrlphenoxyethoxy)phenyl group,
 4-chlorophenyl group, 2,5-dichlorophenyl group, 2,4,6-trimethylphenyl
 group, 3-chlorophenyl group, 3-methylphenyl group, 3-methoxyphenyl group,
 3-butoxyphenyl group, 3-cyanophenyl group, 3-(2-ethylhexyloxy)phenyl
 group, 3,4-dichlorophenyl group, 3,5-dichlorophenyl group,
 3,4-dimethoxyphenyl group, 3-(dibutylaminocarbonylmethoxy)phenyl group,
 4-cyanophenyl group, 4-methylphenyl group, 4-methoxyphenyl group,
 4-butoxyphenyl group, 4-(2-ethylhexyloxy)phenyl group, 4-benzylphenyl
 group, 4-aminosulfonylphenyl group, 4-N,N-dibutylaminosulfonylphenyl
 group, 4-ethoxycarbonylphenyl group, 4-(2-ethylhexylcarbonyl)phenyl group,
 4-fluorophenyl group, 3-acetylphenyl group, 2-acetylaminophlenyl group,
 4-(4-chlorophenylthio)phenyl group,
 4-(4-methylphenyl)thio-2,5-butoxyphenyl group,
 4-(N-benzyl-N-methylamino)-2-dodecyloxycarbonylphenyl group and the like.
 Likewise, the above groups may further be substituted by an alkyloxy
 group, alkylthio group, substituted phenyl group, cyano group, substituted
 amino group, halogen atom, heterocyclic group or the like.
 In the general formula (6), R.sup.17 and R.sup.18 each independently
 represents a substituted or unsubstituted alkyl group, or a substituted or
 unsubstituted aryl group. R.sup.17 and R.sup.18 may be the same or
 different from each other.
 Examples of the substituent thereof include an alkyl group, alkoxy group,
 alkylthio group, aryl group, aryloxy group, arylthio group, acyl group,
 alkoxycarbonyl group, carbamoyl group, carboamide group, sulfonyl group,
 sulfamoyl group, sulfonamide group, ureide group, halogen group, amino
 group, heterocyclic group and the like.
 When R.sup.17 and R.sup.18 each independently represents an alkyl group, an
 alkyl group having 1 through 18 carbon atoms is preferable as the alkyl
 group, and examples thereof include, but are not particularly limited to,
 a methyl group, trifluoromethyl group, ethyl group, propyl group,
 isopropyl group, butrl group, sec-butyl group, t-butyl group, pentyl
 group, isopentyl group, cyclopentyl group, hexyl group, cyclohexyl group,
 octyl group, t-octyl group, 2-ethylhexyl group, nonyl group, octadecyl
 group, benzyl group, 4-methoxybenznyl group, triphenylmethyl group,
 ethoxycarbonylmethyl group, butoxycarbonylmethyl group,
 2-ethylhexxyloxycarbonylmethyl group, 2',4'-diisopentylphenyloxymethyl
 group, 2',4'-di-t-butylphenyloxymethyl group, dibenizlaminocarbonylmethyl
 group, 2,4-di-t-amylphenyloxypropyl group, ethox,carbonylpropyl group,
 1-(2',4'-di-t-amylphenyloxy)propyl group, acetylaminoethyl group,
 2-(N,N-dimethylamino)ethyl group, 2-(N,N-diethylamino)propyl group,
 methanesulfonylaminopropyl group, acetylaminoethyl group,
 2-(N,N-dimethylamino)ethyl group, 2-(N,N-diethylamino)propyl group and the
 like.
 When R.sup.17 and R.sup.18 each independently represents an aryl group, an
 aryl group having 6 through 30 carbon atoms is preferable as the aryl
 group, and examples thereof include a phenyl group, 2-methylphenyl group,
 2-chlorophenyl group, 2-methoxyphenyl group, 2-butoxyphenyl group,
 2-(2-ethylhexyloxy)phenyl group, 2-octyloxyphenyl group,
 3-(2,4-di-t-pentylphenoxyethoxy)phenyl group, 4-chlorophenyl group,
 2,5-dichlorophenyl group, 2,4,6-trimethylphenyl group, 3-chlorophenyl
 group, 3-methylphenyl group, 3-methoxyphenyl group, 3-butoxyphenyl group,
 3-cyanophenyl group, 3-(2-ethylhexyloxy)phenyl group, 3,4-dichlorophenyl
 group, 3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group,
 3-(dibutylaminocarbonylmethoxy)phenyl group, 4-cyanophenyl group,
 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxyphenyl group,
 4-(2-ethylhexyloxy)phenyl group, 4-benzylphenyl group,
 4-aminosulfonylphenyl group, 4-N,N-dibutylaminosulfonylphenyl group,
 4-ethoxycarbonylphenyl group, 4-(2-ethylhexylcarbonyl)phenyl group,
 4-fluorophenyl group, 3-acetylphenyl group, 2-acetylaminophenyl group,
 4-(4-chlorophenylthio)phenyl group,
 4-(4-methylphenyl)thio-2,5-butoxyphenyl group,
 4-(N-benzyl-N-methylamino)-2-dodecyloxycarbonylphenyl group and the like.
 Likewise, the above groups may further be substituted by an alkyloxy
 group, alkylthio group, substituted phenyl group, cyano group,
 substituited amino group, halogen atom, heterocyclic group or the like.
 In the general formulae (4) through (6), X.sup.- represents an acid anion,
 and examples of the acid anion include polyfluoroalkylcarboxylic acids
 having 1 through 9 carbon atoms, polyfluoalkylsulfonic acids having 1
 through 9 carbon atoms, boron tetrafluoride, tetraphenylboron,
 hexafluorophosphoric acid, aromatic carboxylic acids, aromatic sulfonic
 acids and the like. Hexafluorophosphoric acid is preferable in view of
 crystallinity.
 Examples of the diazonium salt compounds represented by the general
 formulae (4) through (6) include, but are not limited to, the following
 compounds.
 ##STR384##
 ##STR385##
 In the present invention, the diazonium salt compounds represented by the
 general formulae (4) through (6) may be used alone, or two or more types
 may be used in combination. Further, the diazonium salt compounds
 represented by the general formulae (4) through (6) may also be used
 together with known diazonium salt compounds in accordance with various
 objects such as hue control and the like.
 The diazonium salt compound used in the present invention in the
 heat-sensitive recording layer is preferably contained in an amount of
 from 0.02 through 3 g/m.sup.2, and more preferably from 0.1 through 2
 g/m.sup.2.
 The diazonium salt compound used in the present invention is preferably
 encapsulated in microcapsules from the standpoint of storability. The
 method for preparing the microcapsules is not particularly limited, and
 the microcapsules can be prepared by a conventionally known method using a
 wall material such as gelatin, polyurea, polyurethane, polyimide,
 polyester, polycarbonate, melamine or the like. Of these wall materials,
 polyurethane and polyurea are preferable from the standpoint of color
 forming property and storability. Details of methods for preparing the
 microcapsules are described in Japanese Patent Application Laid-Open
 (JP-A) No. 2-141279 and the like.
 Further, when preparing the microcapsules, an organic solvent having a high
 boiling point may be used as a dispersion solvent of the diazonium salt
 compound. The organic solvent is not particularly limited, and
 conventionally known solvents such as alkyl phthalate, phosphoric ester,
 citrate, benzoate, alkylamide, fatty ester, trimesilate and the like can
 be used. Details thereof are described in Japanese Patent Application
 Laid-Open (JP-A) No. 7-17145 and the like.
 Other Components
 In the present invention, it is preferable to use organic bases such as
 tertiary amines, piperidines, piperazines, amidines, formamidines,
 pyridines, guanidines, morpholines and the like for the purpose of
 accelerating the coupling reaction.
 Specific examples of the organic bases include piperazines such as
 N,N'-bis(3-phenoxy-2-hydroxypropyl)piperazine,
 N,N'-bis[3-(p-methylphenoxy)-2-hydroxypropyl]piperazine,
 N,N'-bis[3-(p-methoxyphenoxy)-2-hydroxypropyl]piperazine,
 N,N'-bis(3-phenylthio-2-hydroxypropyl)piperazine,
 N,N'-bis[3-(.beta.-naphthoxy)-2-hydroxypropyl]piperazine,
 N-3-(.beta.-naphthoxy)-2-hydroxypropyl-N'-methylpiperazine,
 1,4-bis{[3-(N-methylpiperadino)-2-hydroxy]propyloxy}benzene and the like,
 morpholines such as N-[3-(.beta.-naphthoxy)-2-hydroxy]propylmorpholine,
 1,4-bis[(3-morpholino-2-hydroxy)propyloxy]benzene,
 1,3-bis[(3-morpholino-2-hydroxy)propyloxy]benzene and the like,
 piperidines such as N-(3-phenoxy-2-hydroxypropyl)piperidine,
 N-dodecylpiperidine and the like, triphenylguanidine,
 tricyclohexylguanidine, dicyclohexylphenylguanidine,
 2-N-methyl-N-benzylaminoethyl 4-hydroxybenzoate,
 2-N,N'-di-n-butylaminoethyl 4-hydroxybenzoate,
 4-(3-N,N'-dibutylaminopropoxy)benzenesulfonamide,
 4-(2-N,N'-dibutylaminoethoxycarbonyl)phenoxy acetic amide and the like.
 Details thereof are described in Japanese Patent Application Laid-Open
 (JP-A) Nos. 57-123086, 60-49991 and 60-94381, Japanese Patent Application
 Nos. 7-228731, 7-235157 and 7-235158, and the like. The organic bases
 described above may be used alone, or two or more types may, be used in
 combination. The amount of the organic base to be used in the present
 invention is not particularly limited, but preferably is in a range from 1
 through 30 mol per one mol of the diazonium salt compound.
 In the present invention, a color forming assistant can also be added in
 addition to the pyrrolo[1,2-a]pyrimidine compound represented either by
 the general formula (1), (2) or (3), for the purpose of accelerating the
 color forming reaction.
 Examples of the color forming assistant include phenol derivatives,
 naphthol derivatives, alkoxy-substituted benzenes, alkoxy-substituted
 naphthalenes, hydroxy compounds, carboxylic amide compounds, sulfonamide
 compounds and the like. It is believed that the above compounds lower the
 melting point of the coupler or the basic substance, or improve the heat
 permeability of the microcapsule walls, resulting in high density of the
 formed color.
 Method of Preparing a Heat-sensitive Recording Layer
 The heat-sensitive recording layer of the present invention can be formed
 by preparing a coating solution that contains at least one type of the
 pyrrolo[1,2-a]pyrimidine compound selected from the
 pyrrolo[1,2-a]pyrimidine compounds represented by the general formula (1),
 (2) and (3), the diazonium salt compound and other additives, which is
 then coated on the substrate such as paper, synthetic film or the like by
 a coating method such as bar coating, blade coating, air knife coating,
 gravure coating, roll coating, spray coating, dip coating, curtain coating
 or the like, and is dried. A solid content of the heat-sensitive recording
 layer is approximately from 2 through 30 g/m.sup.2.
 The binder used in the present invention is not particularly limited, and
 conventionally knowan binders can be used such as polyvinyl alcohol,
 hydroxethylcellulose, methylcellulose, carboxymethylcellulose, gelatin,
 styrene-acrylic acid copolymer and the like. Details thereof are described
 in Japanese Patent Application Laid-Open (JP-A) No. 2-141279 and the like.
 In addition, various organic or inorganic pigments, various stabilizers,
 antioxidants and the like can also be added if necessary.
 In the heat-sensitive recording material of the present invention, as
 described in the above method, at least one type of the
 pyrrolo[1,2-a]pyrimidine compound selected from the
 pyrrolo[1,2-a]pyrimidine compounds represented by the general formulae
 (1), (2) and (3), the diazonium salt compound and the like may be
 contained in the same layer, or may be contained in separate layers that
 are layered one upon the other.
 Substrate
 Conventionally known substrates can be used for the substrate used in the
 present invention. Specific examples thereof include neutral paper, acidic
 paper, recycled paper, polyolefine resin-laminated paper, synthetic paper,
 polyester film, cellulose derivative films such as triacetic cellulose
 film and the like, polyolefin films such as polystyrene film,
 polypropylene film, polyethylene film and the like, and they can be used
 alone, or two or more types can be laminated together for use.
 The thickness of the substrate is approximately from 20 through 200 .mu.m.
 Further, there can also be provided an intermediate layer between the
 substrate and the heat-sensitive recording layer. Description thereof can
 be found in Japanese Patent Application Laid-Open (JP-A) No. 61-54980 and
 the like.
 Other Layers and the Like
 In the heat-sensitive recording layer of the present invention, a
 protective layer is preferably provided on the heat sensitive-recording
 layer, and the protective layer is preferably laminated. The protective
 layer is formed from a water-soluble polymer, a pigment and the like. To
 achieve both light resistance and light stability in the protective layer,
 a compound having a function of controlling ultraviolet ray transmittance
 is preferably contained in the protective layer. Details of a
 heat-sensitive recording material containing the compound having a
 function of controlling ultraviolet ray transmittance are described in
 Japanese Patent Application Laid-Open (JP-A) No. 7-276808.
 The heat-sensitive recording material of the present invention is not
 limited to the single color but includes a multi-color heat-sensitive
 recording material as well. Details of the multi-color heat-sensitive
 recording material are described in Japanese Patent Application Laid-Open
 (JP-A) Nos. 4-135787, 4-144784, 4-144785, 4-194842, 4-247447, 4-247448,
 4-340540, 4-340541, 5-34860 and the like.
 Specifically, the multi-color heat-sensitive recording material can be
 obtained by laminating heat-sensitive recording layers that form colors in
 different hues. The layer structure is not particularly limited, but one
 example thereof is a multi-color heat-sensitive recording material
 prepared by laminating two heat-sensitive recording layers (B layer, C
 layer), each of the layers obtained by combining a diazonium salt compound
 having a light-sensitive wavelength that differs from that of the other
 layer with a coupler that with heating reacts with the diazonium salt
 compound to form color of a hue that differs from that of the other layer,
 and a heat-sensitive recording layer (A layer) obtained by combining an
 electron donating colorless dye with an electron receiving compound.
 Specifically, the material comprises a substrate on which are provided a
 first heat-sensitive recording layer (the A layer) containing the electron
 donating colorless dye and the electron receiving compound, a second
 heat-sensitive recording layer (the B layer) containing the diazonium salt
 compound having a maximum absorption wavelength of 360 nm.+-.20 nm and the
 coupler that forms color by reacting with the diazonium salt compound
 during heating, and a third heat-sensitive recording layer (the C layer)
 containing a diazonium salt compound having a maximum absorption
 wavelength of 400 nm.+-.20 nm and the coupler that forms color by reacting
 with the diazonium salt compound during heating. In the above example, if
 formed color hues in the respective heat-sensitive recording layers are
 selected such that the three primary colors in subtractive color mixing,
 i.e., yellow, magenta and cyan, are obtained, full color image recording
 is made possible.
 To record by using the above-described multi-color heat-sensitive recording
 material, first, the third heat-sensitive recording layer (the C layer) is
 heated to allow the diazonium salt and the coupler contained in the layer
 to form color. Then, the unreacted diazonium salt compound contained in
 the C layer is decomposed and fixed by irradiation of light having a
 wavelength of 400.+-.20 nm. Thereafter, heat sufficient for color
 formation of the second heat-sensitive recording layer (the B layer) is
 applied to allow the diazonium salt compound and the coupler contained in
 the layer to form color. At this time, although the C layer is
 simultaneously heated significantly, it does not form color since the
 diazonium salt compound has already been decomposed (has been fixed bar
 light) and the color forming ability is lost. Further, the diazonium salt
 compound contained in the B layer is decomposed by irradiation of light
 having a wyavelength of 360.+-.20 nm. Lastly, heat sufficient for color
 formation of the first heat-sensitive recording layer (the A layer) is
 applied to form color. At this time, although the C and B heat-sensitive
 recording layers are also heated significantly, they do not form color
 since the diazonium salt compounds have already been decomposed and their
 color forming abilities are lost.
 Further, all of the heat-sensitive recording layers (the A layer, the B
 layer and the C layer, in this order from the upper layer) can be
 heat-sensitive recording layers that are obtained by combining three kinds
 of diazonium salt compounds having different light-sensitive wavelengths,
 with couplers that form colors in different hues by reacting with the
 respective diazonium salt compounds during heating. In particular, by
 setting the yellow layer having a low luminosity factor as the lowermost
 layer, effects on images due to roughness on the surface of the substrate
 can be reduced so as to improve image quality. When all of the
 heat-sensitive recording layers (the A layer, the B layer and the C layer)
 are diazo-based heat-sensitive recording layers, it is necessary to carry
 out light-fixing of the A layer and the B layer after color formation.
 There is no need to carry out light-fixing for the C layer.
 Various fluorescent lamps, xenon lamps, mercury lamps and the like can be
 used as the light source for fixing used in the above-described fixing by
 light. It is preferable that the emission spectrum thereof approximately
 coincides with the absorption spectrum of the diazonium salt compound used
 in the heat-sensitive material since then efficient light-fixing is made
 possible.
 Further, when recording on the heat-sensitive recording material of the
 present invention, the heat-scnsitive recording material can also be used
 as a light-sensitive material of a thermal developing type, by which an
 image can be obtained by exposing the material through an original,
 decomposing the diazonium salt compounds at portions other than the image
 formed portions to form a latent image, and thereafter, heating the entire
 material.

EXAMPLES
 Referring now to the following Examples, the present invention will be
 described further in detail, but the scope thereof will not be limited by
 the following Examples.
 It should be noted that in Examples, all "parts" are "parts by weight". The
 numbers in parentheses after "coupler" are the numbers in parentheses in
 Tables 1 though 7 in which specific examples of couplers are listed.
 Pyrrolo[1,2-a]pyrimidine Compound Represented by the General Formula (1) or
 (2)
 Example 1
 Synthesis of
 2-(4-chlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-amin
 o-6-acetyl-pyrrolo[1,2-a]pyrimidine (coupler (6)):
 10 g (19.5 mmol) of
 2-(4-chlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-amin
 o-pyrrolo[1,2-a]pyrimidine was dissolved in 60 ml of tetrahydrofuran
 (heated to 50.degree. C.). To this was added dropwise 7.7 g (97.7 mmol) of
 acetylchloride at 50.degree. C. Then, the solution was stirred for 7 hours
 while being refluxed. After it was cooled, water was added to the
 resulting reaction solutioin. Then, the reaction product was extracted
 with ethyl acetate, washed and dried. After the solvent was distilled off,
 methanol was added to the residue, and the precipitated solid was filtered
 out. Further, the filtered solid was washed first by methanol and then by
 hexane, to obtain 6.5 g of
 2-(4-chlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-amin
 o-6-acetyl- pyrrolo[1,2-a]pyrimidine in the form of a white solid (yield:
 58%).
 The melting point was 195.degree. C. The results of the analysis are given
 below.
 .sup.1 H-NMR(CDCl.sub.3); .delta.: 12.6 (s, 1H); 11.20(s, 1H); 9.50 (brs,
 1H); 7.36 (d, 2H); 7.27 (d, 2H); 5.80 (s, 1H); 2.73 (s, 3H); 1.10 through
 1.35 (m); 0.95 through 1.05 (m); 0.77 (s, 21H); 0.42 through 0.58 (m).
 Example 2
 Synthesis of
 2-(4-chlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-amin
 o-6-phenoxyacetyl-pyrrolo[1,2-a]pyrimidine (coupler (7)):
 10 g (19.5 mmol) of
 2-(4-chlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-amin
 o-pyrrolo[1,2-a]pyrimidine was dissolved in 60 ml of tetrahydrofuran
 (heated to 50.degree. C.). To this was added dropwise 16.6 g (97.7 mmol)
 of phenoxyacetylchloride at 50.degree. C. Then, the solution was stirred
 for 2 hours while being refluxed. After it was cooled, water was added to
 the resulting reaction solution. Then, the reaction product was extracted
 with ethyl acetate, washed and dried. Thereafter, the solvent was
 distilled off. The residue was recrystalized by ethyl acetate/methanol, to
 obtain 9.4 g of
 2-(4-chlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-amin
 o-6-phenoxyacetyl-pyrrolo[1,2-a]pyrimidine in the form of a white solid
 (yield: 74%).
 The melting point was 192.degree. C. The results of the analysis are given
 below.
 .sup.1 H-NMR (CDCl.sub.3); .delta.: 12.60 (s, 1H); 11.20 (s, 1H); 9.50
 (brs, 1H); 7.37 (d, 2H); 7.23 through 7.30 (m, 4H); 6.91 through 6.98 (m,
 3H); 5.81 (s, 1H); 5.46 (s, 2H); 1.10 through 1.35 (m); 0.95 through 1.05
 (m); 0.76 (s, 2H); 0.42 through 0.58 (m).
 Example 3
 Synthesis of
 2-(3,4-dichlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-
 amino-6-(4-methylphenyl)sulfonylcarbamoyl-pyrrolo[1,2-a]pyrimidine (coupler
 (18)):
 1.09 g (2 mmol) of
 2-(3,4-dichlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-
 amino-pyrrolo[1,2-a]pyrimidine was dissolved in 10 ml of tetrahydrofuran.
 To this was added dropwise 0.512 g (2.6 mmol) of
 p-toluenesulfonylisocyanate. Then, the solution was stirred for 30 minutes
 at room temperature. Water was added to the resulting reaction solution.
 Then, the reaction product was extracted with ethyl acetate, washed and
 dried. After being distilled off, the solvent was purified by silica gel
 column chromatography (hexane/ethyl acetate), to obtain 0.89 g of
 2-(3,4-dichlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-
 amino-6-(4-methylphenyl)sulfonylcarbamoyl-pyrrolo[1,2-a]pyrimidine in the
 form of a white solid (yield: 60%).
 The melting point was 298.degree. C. (dec.). The results of the analysis
 are given below.
 .sup.1 H-NMR (CDCl.sub.3); .delta.: 12.58 (s, 1H); 11.20 (s, 1H); 9.47
 (brs, 1H); 8.20 (brs, 1H); 7.99 (d, 2H); 7.47 (d, 1H); 7.42 (d, 1H); 7.30
 (d, 2H); 7.16 (dd, 1H); 7.05 (s, 1H); 5.85 (s, 1H); 2.42 (s, 3H); 1.20
 through 1.40 (m); 1.00 through 1.10 (m); 0.84 (s, 18H); 0.72 (d, 3H); 0.40
 through 0.50 (m).
 Example 4
 Synthesis of
 2-(3,4-dichlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-
 amino-6-phenylsulfonylcarbamoyl-pyrrolo[1,2-a]pyrimidine (coupler (11)):
 The above coupler (11) was obtained in the same manner as in Example 3
 except that instead of the p-toluenesulfonylisocyanate used in Example 3,
 phenylsulfonylisocyanate was used (yield: 63%).
 The melting point was 210.degree. C. The results of the analysis are given
 below.
 .sup.1 H-NMR (CDCl.sub.3); .delta.: 12.60 (s, 1H); 11.20 (s, 1H); 9.45
 (brs, 1H); 8.30 (brs, 1H); 8.13 (dd, 2H); 7.50 through 7.65 (m, 3H); 7.49
 (d, 1H); 7.41 (d, 1H); 7.17 (dd, 1H); 7.08 (s 1H); 5.87 (s, 1H); 1.20
 through 1.40 (m); 1.00 through 1.08 (m); 0.80 (s, 18H); 0.72 (d, 3H); 0.40
 through 0.53 (m).
 Example 5
 Synthesis of
 2-(3,4-dichlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-
 amino6-(4chlorophenyl)sulfonylcarbamoyl-pyrrolo[1,2a]pyrimidine (coupler
 (10)):
 The above coupler (10) was obtained in the same manner as in Example 3
 except that instead of the p-toluenesulfonylisocyanate used in Example 3,
 p-chlorophenylsulfonylisocyanate was used (yield: 63%)
 The melting point was 209.degree. C. The results of the analysis are given
 below.
 .sup.1 H-NNMR (CDCl.sub.3); .delta.: 12.65 (s, 1H); 11.27 (s, 1H); 9.40
 (brs, 1H); 8.35 (brs, 1H); 8.05 (d, 2H); 7.49 (d, 1H); 7.48 (d, 2H); 7.40
 (d, 1H); 7.15 (dd, 1H); 7.05 (s, 1H); 5.86 (s, 1H); 1.20 through 1.40 (m);
 1.00 through 1.10 (m); 0.84 (s, 18H); 0.71 (d, 3H); 0.40 through 0.53 (m).
 Example 6
 Synthesis of
 2-(3,4-dichlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-
 amino-6-ethoxycarbonylcarbamoyl-pyrrolo[1,2-a]pyrimidine (coupler (26)):
 The above coupler (26) was obtained in the same manner as in Example 3
 except that instead of the p-toluenesulfonylisocyanate used in Example 3,
 ethoxycarbonylisocyanate was used (yield: 50%).
 The melting point was equal to or higher than 300.degree. C. The results of
 the analysis are given below.
 .sup.1 H-NMR (CDCl.sub.3); .delta.: 12.60 (s, 1H); 10.68 (s, 1H); 10.03
 (brs, 1H); 9.31 (brs, 1H); 7.50 (d, 1H); 7.45 (d, 1H); 7.20 (dd, 1H);
 7.08(s, 1H); 5.84 (s, 1H); 4.59 (q, 2H); 1.20 through 1.40 (m); 1.00
 through 1.10 (mm); 0.86 (s, 18H); 0.75 (d, 3H); 0.40 through 0.54 (m).
 Example 7
 Synthesis of coupler (49):
 5.12 g (10 mmol) of
 2-(4-chlorophenyl)-3-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-5-amin
 o-pyrrolo[1,2-a]pyrimidine was dissolved in 50 ml of tetrahydrofuran. To
 this was added dropwise 1.84 g (13 mmol) of chlorosulfonylisocyanate.
 Then, the solution was stirred for 30 minutes at room temperature.
 Thereafter, 1.01 g (10 mmol) of triethylamine was added and stirred for
 another 2 hours at room temperature. Water was added to the resulting
 reaction solution. Then, the reaction product was extracted with ethyl
 acetate, washed and dried. After being distilled off, the solvent was
 purified by silica gel chromatography (hexane/ethyl acetate), to obtain
 2.44 g of the above-described coupler (49) in the form of a white solid
 (yield: 40%).
 The melting point was 202.degree. C. The results of the analysis are given
 below.
 .sup.1 H-NMR (CDCl.sub.3); .delta.: 11.09 (s, 1H); 10.14 (brs, 1H); 9.35
 (brs, 1H); 7.37 (d, 2H); 7.30 (d, 2H); 7.07 (s, 1H); 5.88 (s, 1H); 1.20
 through 1.40 (m); 1.00 through 1.10 (m); 0.84 (s, 18H); 0.80 (d, 3H); 0.47
 through 0.60 (m).
 Heat-sensitive Recording Material
 Example 8
 Preparation of Microcapsule Liquid A:
 To 19 parts of ethyl acetate were added 2.8 parts of a diazonium salt (an
 example compound (5)-1, maximum absorption wavelength: 370 nm) and 10
 parts of tricresyl phosphate, and they were mixed uniformly. Then, to the
 above mixture was added 7.6 parts of Takenate D-110N (manufactured by
 Takeda Chemical Industries Ltd.) as a wall agent, and they were mixed
 uniformly to obtain a liquid I.
 Then, to the above liquid I were added 46 parts of an 8% by weight aqueous
 solution of phthalated gelatin, 17.5 parts of water and 2 parts of a 10%
 aqueous solution of sodium dodecylbenzenesulfonate, and the mixture was
 emulsified and dispersed at 10000 r.p.m. for 10 minutes at a temperature
 of 40.degree. C. To the resultant emulsion was added 20 parts of water and
 the mixture was made uniform, and thereafter, a microcapsule forming
 reaction was made to take place for 3 hours at 40.degree. C. while
 stirring to obtain a microcapsule liquid A. The average particle diameter
 of the microcapsules was from 0.7 through 0.8 .mu.m.
 Preparation of Coupler Emulsified Liquid B:
 To 10.5 parts of ethyl acetate were added 3.0 parts of a coupler (6), 3.0
 parts of triphenylguanidine, 0.5 parts of tricresyl phosphate and 0.24
 parts of diethyl maleate ester to obtain a liquid II.
 Then, 49 parts of a 15% by weight aqueous solution of lime-treated gelatin,
 9.5 parts of a 10% aqueous solution of sodium dodecylbenzenesulfonate and
 35 parts of water were mixed uniformly at 40.degree. C., and to the above
 mixture was added the liquid II, and the mixture was emulsified and
 dispersed at 10000 r.p.m. for 10 minutes at a temperature of 40.degree. C.
 by using a homogenizer. The resultant emulsion was stirred for 2 hours at
 40.degree. C. to remove ethyl acetate, and thereafter, water was added in
 an amount (weight) corresponding to the vaporized ethyl acetate and water,
 so as to obtain a coupler emulsified liquid B.
 Preparation of Heat-sensitive Recording Layer Coating Liquid C:
 3.6 parts of the microcapsule liquid A, 3.3 parts of water and 9.5 parts of
 the coupler emulsified liquid B were uniformly mixed to obtain a
 heat-sensitive recording layer coating liquid C.
 Preparation of Protective Layer Coating Liquid D:
 100 parts of a 6% aqueous solution of itaconic acid-modified polvinyl
 alcohol (trade name: KL-318, manufactured by Kuraray Co., Ltd.) and 10
 parts of a 30% dispersion of an epoxy-modified polyamide (trade name:
 FL-71, manufactured by Toho Chemical Industry Co., Ltd.) were mixed
 together, and into this wias mixed uniformly 15 parts of a 40% dispersion
 of zinc stearate (trade name: Hydrin Z, manufactured by Chuko Yusli K.K.)
 to obtain a protective layer coating liquid D.
 Coating:
 On a substrate for photographic printing paper which substrate was formed
 by laminating polyethylene onto a high quality paper, the heat-sensitive
 recording layer coating liquid C and the protective layer coating liquid D
 were each coated by using a wire bar and dried at 50.degree. C. in that
 order to obtain the intended heat-sensitive recording material. The coated
 amounts in terms of solid components were 8.0 g/m.sup.2 and 1.2 g/m.sup.2,
 respectively.
 Color Forming Test:
 A sample was thermally printed using a thermal head manufactured by Kyocera
 Corp. (KST type) with the pulse width and power applied to the thermal
 head having been determined such that the recording energy per unit area
 was 50 mJ/mm.sup.2. Thereafter, the entire surface of the sample was
 irradiated by light for 15 seconds by using an ultraviolet ray lamp having
 an emission center wavelength of 365 nm and an output of 40 W. The
 resultant densities of the image portions and background portions of the
 sample were measured by a Macbeth densitometer.
 Evaluation of Hue:
 The reflection spectrum of the image portions, whose color was formed with
 a thermal head manufactured by Kyocera Corp. (KST type), was measured
 using a UV/VIS photospectroscope and standarized with the maximum
 absorbance set at 1.0. A lower absorbance within a wavelength range from
 400 through 475 nm means that an excellent cowan color in which there is
 little yellow has been obtained.
 Image Light-resistance Test:
 By using a fluorescent lamp light-resistance tester, the image portions,
 whose color was formed with a thermal head manufactured by Kyocera Corp.
 (KST type), were irradiated by light continuously for 72 hours at 32,000
 lux, and thereafter, the density of the image portions was measured. The
 higher the density of the image portions after irradiation of light, the
 more excellent the image light-resistance.
 Image Fixing Property Test:
 For testing the image fixing property, the background portions (non-printed
 portions) of the fixed sample were thermally printed by using a thermal
 head manufactured by Kyocera Corp. (KST type) with the pulse width and
 power applied to the thermal head having been determined such that the
 recording energy per unit area was 40 mJ/mm.sup.2, and the change in
 density was measured. The lower the density after printing, the more
 excellent the image fixing property.
 Example 9
 A heat-sensitive recording material of Example 9 was prepared and evaluated
 in the same manner as in Example 8 except that the emulsified liquid was
 obtained by using a coupler (7) instead of the coupler (6) used in Example
 8.
 Example 10
 A heat-sensitive recording material of Example 10 was prepared and
 evaluated in the same manner as in Example 8 except that the emulsified
 liquid was obtained by using a coupler (10) instead of the coupler (6)
 used in Example 8.
 Example 11
 A heat-sensitive recording material of Example 11 was prepared and
 evaluated in the same manner as in Example 8 except that the emulsified
 liquid was obtained by using a coupler (11) instead of the coupler (6)
 used in Example 8.
 Example 12
 A heat-sensitive recording material of Example 12 was prepared and
 evaluated in the same manner as in Example 8 except that the emulsified
 liquid was obtained by using a coupler (12) instead of the coupler (6)
 used in Example 8.
 Example 13
 A heat-sensitive recording material of Example 13 was prepared and
 evaluated in the same manner as in Example 8 except that the emulsified
 liquid was obtained by using a coupler (18) instead of the coupler (6)
 used in Example 8.
 Example 14
 A heat-sensitive recording material of Example 14 was prepared and
 evaluated in the same manner as in Example 8 except that the emulsified
 liquid was obtained by using a coupler (26) instead of the coupler (6)
 used in Example 8.
 Example 15
 A heat-sensitive recording material of Example 15 was prepared and
 evaluated in the same manner as in Example 8 except that the emulsified
 liquid asobtained by using a coupler (49) instead of the coupler (6) used
 in Example 8.
 Example 16
 A heat-sensitive recording material of Example 16 was prepared and
 evaluated in the same manner as in Example 13 except that the microcapsule
 liquid was prepared by using an example compound (4)-2 (maximum absorption
 wavelength: 370 nm) instead of the diazonium salt (example compound (5)-1)
 used in Example 13.
 Comparative Example 1
 A heat-sensitive recording material of Comparative Example 1 was prepared
 and evaluated in the same manner as in Example 8 except that the
 emulsified liquid was obtained by using 2-hydroxy-3-naphthoic
 acid[3-(2-ethylhexyloxy)anilide] instead of the coupler (6) used in
 Example 8
 Values of .lambda..sub.max and results of the image light-resistance test
 and image fixing property test of the image portions are given in Table
 17. Data on the absorbance (wavelength range: 400 through 475 nm) of the
 image portions are given in Table 18.
 TABLE 17
 Image fixing
 Image light- property test
 Color- resistance test Density of
 formed Density of image background
 image portions portions
 .lambda..sub.max Before After Before After
 (nm) irradiation irradiation printing printing Hue
 Example 8 658 1.57 1.33 0.07 0.12 cyan
 Example 9 662 1.55 1.31 0.07 0.12 cyan
 Example 10 667 1.58 1.30 0.06 0.11 cyan
 Example 11 666 1.50 1.32 0.06 0.10 cyan
 Example 12 661 1.56 1.31 0.06 0.10 cyan
 Example 13 666 1.55 1.33 0.06 0.10 cyan
 Example 14 660 1.54 1.34 0.07 0.12 cyan
 Example 15 650 1.50 1.31 0.06 0.10 cyan
 Example 16 655 1.52 1.33 0.06 0.10 cyan
 Comparative 632 1.30 0.60 0.08 0.58 blue
 Example 1
 TABLE 18
 Absorbance
 Wavelength Wavelength Wavelength
 (400 nm) (450 nm) (475 nm)
 Example 8 0.15 0.09 0.11
 Example 9 0.16 0.09 0.10
 Example 10 0.13 0.07 0.09
 Example 11 0.12 0.06 0.08
 Example 12 0.13 0.07 0.08
 Example 13 0.12 0.06 0.08
 Example 14 0.14 0.06 0.08
 Example 15 0.13 0.08 0.09
 Example 16 0.14 0.07 0.09
 Comparative 0.28 0.25 0.22
 Example 1
 From the above results, it can be understood that the heat-sensitive
 recording material using as the coupler the pyrrolo[1,2-a]pyrimidine
 compound represented by the general formulae (1) or (2) of the present
 invention has high density of the formed color. In the image portions,
 there is little absorption of yellow color, and an excellent cyan color
 can be obtained. It is further evident that, even after irradiation with a
 fluorescent lamp, there is little decrease in density of the image
 portions and the image light-resistance is excellent. Moreover, when the
 background portions of a sample that has been subjected to image fixing
 are again thermally, printed, there is little color formation and the
 image fixingy property is excellent.
 Pyrrolo[1,2-a]pyrimidine Compound Represented by the General Formula (3)
 It should be noted that in the Examples, all "parts" are "parts by weight".
 The numbers in parentheses after "coupler" are the numbers in parentheses
 in Tables 8 though 16 in which specific examples of couplers are listed.
 Example 17
 Synthesis of Coupler (50):
 10 g (19.5 mmol) of
 7-(4-chlorophenyl)-8-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-2-amin
 o-pyrrolo[1,2-a]pyrimidine-4-on was added to 60 ml of acetonitrile and
 cooled to 0 through 5.degree. C. To this, 3.6 g (25.4 mmol) of
 chlorosulfonylisocyanate was added dropwise in such a manner as to keep
 the reaction temperature below 25.degree. C. Then, the solution was cooled
 to room temperature and was stirred for 3 hours. Further, the solution was
 cooled again to 0 through 5.degree. C. To this, 5.15 g (58.5 mmol) of
 N,N'-dimethylaminoethylamine was added dropwise in such a manner as to
 keep the reaction temperature below 25.degree. C. Then, the solution was
 cooled to room temperature and was stirred for 1.5 hours.
 Water was added to the resulting reaction solution. Then, the reaction
 product was extracted with ethyl acetate, washed with a saturated sodium
 chloride solution and dried. The ethyl acetate was distilled off under
 reduced pressure. The residue was fractionated by silica gel
 chrornatography. Methanol was added to the fraction, and the precipitated
 solid was filtered out to obtain 7.4 g of an example compound (50) in the
 form of a pale yellow solid (yield: 54%).
 m.p. 115.5.degree. C.; .sup.1 H-NMR (CDCl.sub.3) 7.4 (d 2H) 7.25 (d 2H)
 5.83 (s 1H) 3.2 (m 2H) 2.55 (m 2H) 0.4 through 1.4 (m 28H).
 Example 18
 Synthesis of Coupler (58):
 15 g (27.4 mmol) of
 7-(3,4-dichlorophenyl)-8-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-2-
 amino-pyrrolo[1,2-a]pyrimidine-4-on was added to 80 ml of acetonitrile and
 cooled to 0 through 5.degree. C. To this, 5 g (35.3 mmol) of
 chlorosulfonylisocyanate was added dropwise in such a manner as to keep
 the reaction temperature below 25.degree. C. Then, the solution was cooled
 to room temperature and was stirred for 3 hours. Further, the solution was
 cooled again to 0 through 5.degree. C. To this, 8.4 g (82.2 mmol) of
 trimethylethylenediamine was added dropwise in such a manner as to keep
 the reaction temperature below 25.degree. C. Then, the solution was cooled
 to room temperature and was stirred for 1.5 hours.
 Water was added to the resulting reaction solution. Then, the reaction
 product was extracted with ethyl acetate, washed with a saturated sodium
 chloride solution and dried. The ethyl acetate was distilled off under
 reduced pressure. The residue was fractionated by silica gel
 chromatography. Methanol was added to the fraction, and the precipitated
 solid was filtered out to obtain 10.1 g of an example compound (58) in the
 form of a white solid (yield: 49%).
 m.p. 149.4.degree. C.; .sup.1 H-NMR (CDCl.sub.3) 7.5 (d 2H) 7.1 (d 2H) 7.18
 through 7.20 (d-d 1H) 7.05 (s 1H) 5.84 (s 1H) 3.5 (m 2H) 3.0 (s 3H) 2.63
 (m 2H) 2.37 (s 6H) 0.4 through 1.4 (m 28H).
 Example 19
 Synthesis of Coupler (60):
 15 g (27.4 mmol) of
 7-(3,4-dichlorophenyl)-8-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-2-
 amino-pyrrolo[1,2-a]pyrimidine-4-on was added to 80 ml of acetonitrile and
 cooled to 0 through 5.degree. C. To this, 5 g (35.3 mmol) of
 chlorosulfonylisocyanate was added dropwise in such a manner as to keep
 the reaction temperature below 25.degree. C. Then, the solution was cooled
 to room temperature and was stirred for 3 hours. Further, the solution was
 cooled again to 0 through 5.degree. C. To this, 8.2 g (82.2 mmol) of
 N-methylpiperazine was added dropwise in such a manner as to keep the
 reaction temperature below 25.degree. C. Then, the solution was cooled to
 room temperature and was stirred for 1.5 hours.
 Water was added to the resulting reaction solution. Then, the reaction
 product was extracted with ethyl acetate, washed with a saturated sodium
 chloride solution and dried. The ethyl acetate was distilled off under
 reduced pressure. Methanol was added to the residue, and the precipitated
 solid was filtered out to obtain 14.2 g of example compound (60) in the
 form of a white solid (yield: 69%).
 m.p. 136.3.degree. C.;
 .sup.1 H-NMR (CDCl.sub.3) 12.8 (s 1H) 7.5 (d 2H) 7.41 (d 2H) 7.18 through
 7.20 (d-d 1H) 7.03 (s 1H) 3.48 (m 2H) 2.58 (m 2H) 2.40 (s 3H) 0.4 through
 1.4 (mn 28H).
 Example 20
 Synthesis of coupler (66):
 10 g (19.5 mmol) of
 7-(4-chlorophenyl)-8-(2,6-di-t-butyl-4-methyl)cyclohexyloxycarbonyl-2-amin
 o-pyrrolo[1,2-a]pyrimidine-4-on was added to 80 ml of acetonitrile and
 cooled to 0 through 5.degree. C. To this, 5 g (35.3 mmol) of
 chlorosulfonylisocyanate was added dropwise in such a manner as to keep
 the reaction temperature below 25.degree. C. Then, the solution was cooled
 to room temperature and was stirred for 3 hours. Further, the solution was
 cooled again to 0 through 5.degree. C. To this, 5.3 g of N-methyl-aniline
 (49 mmol) was added dropwise in such a manner as to keep the reaction
 temperature below, 25.degree. C. Then, the solution was cooled to room
 temperature and was stirred for 1.5 hours.
 Water was added to the resulting reaction solution. Then, the reaction
 product was extracted with ethyl acetate, washed with a saturated sodium
 chloride solution and dried. The ethyl acetate was distilled off under
 reduced pressure. Methanol was added to the residue, and the precipitated
 solid was filtered out to obtain 10.3 g of an example compound (66) in the
 form of a white solid (yield: 70.7%).
 m.p. 171.4.degree. C,;
 .sup.1 H-NMR (CDCl.sub.3) 12.22 (s 1H) 10.6 (s 1H) 7.24 through 7.45 (m 9H)
 7.02 (s 1H) 5.86 (s 1H) 3.54 (s 3H) 0.4 through 1.4 (m 28H).
 Example 21
 Synthesis of Coupler (68):
 15 g (50.5 mmol) of
 7-phenyl-8-ethoxycarbonyl-2-amino-pyrrolo[1,2-a]pyrimidine-4-on was added
 to 100 ml of acetonitrile and cooled to 0 through 5.degree. C. To this,
 8.6 g (60.8 mmol) of chlorosulfonylisocyanate was added dropwise in such a
 mannier is to keep the reaction temperature below 25.degree. C. Then, the
 solution was cooled to room temperature and was stirred for 3 hours.
 Further, the solution was cooled again to 0 through 5.degree. C. To this,
 13.5 g (126.2 mmol) of N-methyl-aniline was added dropwise in such a
 manner as to keep the reaction temperature below 25.degree. C. Then, the
 solution was cooled to room temperature and was stirred for 1.5 hours.
 Water was added to the resulting reaction solution. Then, the reaction
 product was extracted with ethyl acetate, washed with a saturated sodium
 chloride solution and dried. The ethyl acetate was distilled off under
 reduced pressure. The residue was fractionated by silica gel
 chromatography. Methanol was added to the fraction, and the precipitated
 solid was filtered to obtain 13.8 g of an example compound (68) in the
 form of a white solid (yield: 53.7%).
 m.p. 134.8.degree. C.;
 .sup.1 H-NMR (CDC1.sub.3) 12.42 (s 1H) 10.23 (s 1H) 7.26 through 7.48 (m
 1OH) 7.18 (s 1H) 4.23 (q 2H) 3.53 (s 3H) 1.24 (t 3H).
 Example 22
 Synthesis of Coupler (69):
 15 g (50.5 mmol) of
 7-phenyl-8-ethoxycarbonyl-2-amino-pyrrolo[1,2-a]pyrimidine-4-on was added
 to 100 ml of acetonitrile and cooled to 0 through 5.degree. C. To this,
 8.6 g (60.8 mmol) of chlorosulfonylisocyanate was added dropwise in such a
 manner as to keep the reaction temperature below 25.degree. C. Then, the
 solution was cooled to room temperature and was stirred for 3 hours.
 Further, the solution was cooled again to 0 through 5.degree. C. To this,
 17.0 g (126 mmol) of 3-isopropyl-aniline was added dropwise in such a
 manner as to keep the reaction temperature below 25.degree. C. Then, the
 solution was cooled to room temperature and was stirred for 1.5 hours.
 Water was added to the resulting reaction solution. Then, the reaction
 product was extracted with ethyl acetate, washed with a saturated sodium
 chloride solution and dried. The ethyl acetate was distilled off under
 reduced pressure. The residue was fractionated by silica gel
 chromatography. Methanol was added to the fraction, and the precipitated
 solid was filtered out to obtain 15.1 g of an example compound (69) in the
 form of a pale yellow solid (yield: 55.7%).
 m.p. 220.7.degree. C.;
 .sup.1 H-NMR (CDCl.sub.3) 12.5 (s 1H) 10.81 (s 1H) 8.87 (s 1H) 7.06 through
 7.5 (m 9H) 7.1 (s 1H) 4.1 (q 2H) 2.84 (m 1H) 1.12 (d 6H) 1.06 (t 3H).
 It should be noted that other pyrrolo[1,2-a]pyrimidine compounds can be
 synthesized in the same manner.
 Example 23
 Preparation of Heat-sensitive Recording Material:
 Preparation of Microcapsule Liquid A:
 To 19 parts of ethyl acetate were added 2.8 parts of a diazonium salt
 (example compound (4)-1, maximum absorption wavelength: 370 nm) and 10
 parts of tricresyl phosphate, and they were mixed uniformly. Then, to the
 above mixture was added 7.6 parts of Takenate D-110N (manufactured by,
 Takeda Chemical Industries Ltd.) as a wall agent, and they were mixed
 uniformly to obtain a liquid I.
 Then, to the above liquid I were added 46 parts of an 8% by weight aqueous
 solution of phthalated gelatini, 17.5 parts of water and 2 parts of a 10%
 aqueous solution of sodium dodecylbenzenesulfonate, and the mixture was
 emulsified and dispersed at 10000 r.p.m. for 10 minutes at a temperature
 of 40.degree. C. To the resultant emulsion was added 20 parts of water and
 the mixture was made uniform, and thereafter, a microcapsule forming
 reaction was made to take place for 3 hours at 40.degree. C. while
 stirring to obtain a microcapsule liquid A. The average particle diameter
 of the microcapsules was from 0.7 through 0.8 .mu.m.
 Preparation of Coupler Emulsified Liquid B:
 To 10.5 parts of ethyl acetate were added 3.0 parts of a coupler (an
 example compound (4)), 3.0 parts of triphenylguanidine, 0.5 parts of
 tricresyl phosphate and 0.24 parts of diethyl maleate to obtain a liquid
 II.
 Then, 49 parts of a 15% by weight aqueous solution of lime-treated gelatin,
 9.5 parts of a 10% aqueous solution of sodium dodecylbenzenesulfonate and
 35 parts of water were mixed uniformly at 40.degree. C., and to the above
 mixture was added the liquid II, and the mixture was emulsified and
 dispersed at 10000 r.p.m. for 10 minutes at a temperature of 40.degree. C.
 by using a homogenizer. The resultant emulsion was stirred for 2 hours at
 40.degree. C. to remove ethyl acetate, and thereafter, water was added in
 an amount (weight) corresponding to the vaporized ethyl acetate and water,
 so as to obtain a coupler emulsified liquid B.
 Preparation of Heat-sensitive Recording Layer Coating Liquid C:
 3.6 parts of the microcapsule liquid A, 3.3 parts of water and 9.5 parts of
 the coupler emulsified liquid B were uniformly mixed to obtain a
 heat-sensitive recording layer coating liquid C.
 Preparation of Protective Layer Coating Liquid D:
 100 parts of a 6% aqueous solution of itaconic acid-modified polyvinyl
 alcohol (trade name: KL-318, manufactured by, Kuraray Co., Ltd.) and 10
 parts of a 30% dispersion of an epoxy-modified polyamide (trade name:
 FL-71, manufactured by Toho Chemical Industry Co., Ltd.) were mixed
 together, and into this was mixed uniformly 15 parts of a 40% dispersion
 of zinc stearate (trade name: Hydrin Z, manufactured by Chukyo Yushi K.K.)
 to obtain a protective layer coating liquid D.
 Coating:
 On a substrate for photographic printing paper which substrate was formed
 by laminating polyethylene onto a high quality paper, the heat-sensitive
 recording layer coating liquid C and the protective layer coating liquid D
 were each coated by using a wire bar and dried at 50.degree. C. in that
 order to obtain the intended heat-sensitive recording material. The coated
 amounts in terms of solid components were 8.0 g/m.sup.2 and 1.2 g/m.sup.2,
 respectively.
 Color Forming Test:
 A sample was thermally printed using a thermal head manufactured by Kyocera
 Corp. (KST type) with the pulse width and power applied to the thermal
 head having been determined such that the recording energy per unit area
 was 50 mJ/mm.sup.2. Thereafter, the entire surface of the sample was
 irradiated by light for 15 seconds by using an ultraviolet ray lamp having
 an emission center wavelength of 365 nm and an output of 40 W. The
 resultant densities of the image portions and background portions of the
 sample were measured by a Macbeth densitometer.
 Image Light-resistance Test:
 By using a fluorescent lamp light-rcsistance tester, the image portions,
 whose color was formed with a thermal head manufactured by Kvocera Corp.
 (KST typc), wacre irradiated byd light continuously for 24 hours at 30,000
 lux, and thereafter, the density of the image portions was measured. The
 higher the density of the image portions after irradiation of light, the
 more excellent the image light-resistance.
 Image Fixing Property Test:
 For testing the image fixing property, the background portions (non-printed
 portions) of the fixed sample were thermally printed by using a thermal
 head manufactured by Kyocera Corp. (KST type) with the pulse width and
 power applied to the thermal head having been determined such that the
 recording energy per unit area was 40 mJ/mm.sup.2, and the change in
 density was measured. The lower the density after printing, the more
 excellent the image fixing property.
 Example 24
 A heat-sensitive recording material of Example 24 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (9) instead of the coupler (4)
 used in Example 23.
 Example 25
 A heat-sensitive recording material of Example 25 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (16) instead of the coupler (4)
 used in Example 23.
 Example 26
 A heat-sensitivc recording material of Example 26 was prepared and
 evaluated in the same manneir as in Examplc 23 exccpt that the emulsified
 product was obtained by using a coupler (21) instead of the coupler (4)
 used in Example 23.
 Example 27
 A heat-sensitive recording material of Example 27 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (27) instead of the coupler (4)
 used in Example 23.
 Example 28
 A heat-sensitive recording material of Example 28 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (32) instead of the coupler (4)
 used in Example 23.
 Example 29
 A heat-sensitive recording material of Example 29 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (35) instead of the coupler (4)
 used in Example 23.
 Example 30
 A heat-sensitive recording material of Example 30 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (40) instead of the coupler (4)
 used in Example 23.
 Example 31
 A heat-sensitive recording material of Example 31 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (41) instead of the coupler (4)
 used in Example 23.
 Example 32
 A heat-sensitive recording material of Example 32 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (44) instead of the coupler (4)
 used in Example 23.
 Example 33
 A heat-sensitive recording material of Example 33 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (46) instead of the coupler (4)
 used in Example 23.
 Example 34
 A heat-sensitive recording material of Example 34 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using the coupler (49) instead of the coupler (4)
 used in Example 23.
 Example 35
 A heat-sensitive recording material of Example 35 was prepared and
 evaluated in the same mannier as in Example 23 except that the emulsified
 product was obtained by using a coupler (50) instead of the coupler (4)
 used in Example 23.
 Example 36
 A heat-sensitive recording material of Example 36 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (55) instead of the coupler (4)
 used in Example 23.
 Example 37
 A heat-sensitive recording material of Example 37 was prepared and
 evaluated in the same manner as in Example 23 except that the microcapsule
 liquid was prepared by using an example compound (3)-2 (maximum absorption
 wavelength: 365 nm) instead of the diazonium salt (the example compound
 (4)-1) used in Example 23.
 Example 38
 A heat-sensitive recording material of Example 38 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (56) instead of the coupler (4)
 used in Example 23.
 Example 39
 A heat-sensitive recording material of Example 39 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (58) instead of the coupler (4)
 used in Example 23.
 Example 40
 A heat-sensitive recording material of Example 40 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (59) instead of the coupler (4)
 used in Example 23.
 Example 41
 A heat-sensitive recording material of Example 41 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (60) instead of the coupler (4)
 used in Example 23.
 Example 42
 A heat-sensitive recording material of Example 42 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (61) instead of the coupler (4)
 used in Example 23.
 Example 43
 A heat-sensitive recording material of Example 43 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (66) instead of the coupler (4)
 used in Example 23.
 Example 44
 A heat-sensitive recording material of Example 44 was prepared and
 evaluated in the same manner as in Examplc 23 except that the emulsified
 product was obtained by using a coupler (67) instead of the coupler (4)
 used in Example 23.
 Example 45
 A heat-sensitive recording material of Example 45 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (68) instead of the coupler (4)
 used in Example 23.
 Example 46
 A heat-sensitive recording material of Example 46 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (69) instead of the coupler (4)
 used in Example 23.
 Example 47
 A heat-sensitive recording material of Example 47 was prepared and
 evaluated in the same manner as in Example 23 except that the emulsified
 product was obtained by using a coupler (72) instead of the coupler (4)
 used in Example 23.
 Comparative Example 2
 A heat-sensitive recording material of Comparative Example 2 was prepared
 and evaluated in the same manner as in Example 23 except that the
 emulsified product was obtained by using 2-hydroxy-3-naplhthoic
 acid[3-(2-ethylhexyloxy)anilide] instead of the coupler (4) used in
 Example 23.
 Values of .lambda..sub.max and results of the image light-resistance test
 and fixing property test of the image portions are given in Tables 19 and
 20.
 TABLE 9
 Image fixing
 Image property test
 light- Density of
 Color- resistance background
 formed Color Density portions
 image .lambda..sub.max forming after Before After
 Examples (nm) property irradiation printing printing
 Example 23 685 1.78 1.55 0.06 0.08
 Example 24 695 1.79 1.54 0.07 0.09
 Example 25 684 1.80 1.61 0.06 0.09
 Example 26 697 1.77 1.54 0.07 0.09
 Example 27 690 1.70 1.50 0.07 0.10
 Example 28 702 1.72 1.51 0.08 0.10
 Example 29 665 1.78 1.52 0.07 0.09
 Example 30 674 1.77 1.50 0.09 0.11
 Example 31 661 1.80 1.62 0.07 0.10
 Example 32 660 1.81 1.61 0.08 0.10
 Example 33 658 1.70 1.51 0.07 0.09
 Example 34 670 1.72 1.51 0.08 0.11
 Example 35 671 1.68 1.48 0.09 0.12
 TABLE 20
 Image fixing
 Image property test
 light- Density of
 Color- resistance background
 Examples, formed Color Density portions
 Comparative image .lambda..sub.max forming after Before After
 Examples (nm) property irradiation printing printing
 Example 36 655 1.81 1.62 0.06 0.09
 Example 37 698 1.83 1.64 0.06 0.08
 Example 38 651 1.84 1.63 0.06 0.09
 Example 39 667 1.81 1.60 0.06 0.09
 Example 40 660 1.81 1.61 0.07 0.10
 Example 41 665 1.79 1.58 0.07 0.09
 Example 42 654 1.80 1.59 0.06 0.09
 Example 43 653 1.83 1.61 0.06 0.08
 Example 44 656 1.79 1.60 0.07 0.08
 Example 45 645 1.85 1.64 0.06 0.08
 Example 46 647 1.84 1.65 0.06 0.08
 Example 47 657 1.77 1.55 0.07 0.09
 Comparative 639 1.23 0.55 0.09 0.55
 Example 2
 From the results described above, it is made evident that a heat-sensitive
 recording material of a purple-to-cyan color forming type, which uses as a
 coupler a pyrrolo[1,2-a]pyrimidine compound represented by the general
 formula (3) has high density of the formed color. It is further evident
 that, even after irradiation with a fluorescent lamp, there is little
 decrease in density of the image portions and the image light-resistance
 is excellent. Moreover, when the background portions of a sample that has
 been subjected to image fixing are again thermally printed, there is
 little color formation and the image fixing property is excellent.
 According to the present invention, there can be provided a novel
 pyrrolo[1,2-a]pyrimidine compound that, when coupled with a diazonium salt
 serving as a coupler, can not only provide excellent color forming
 property but can also produce a cyan dyethat has low absorption of yellow
 color. Further, in accordance with the present invention, by combining the
 above pyrrolo[1,2-a]pyrimidine compound with a diazonium salt compound,
 there can be provided a novel diazo heat-sensitive recording material of a
 cyan color forming type having excellent shelf life, image
 light-resistance and image fixing property in addition to the
 above-described properties.