Heterocyclic compounds, their production, and medicaments containing them

Abstract: Compounds of formula I and salts thereof are useful for the treatment and prophylaxis of allergic diseases. Production and use of the compounds is described.

Description: This invention relates to the medicinally useful compounds of the following general formula (I) and the salts thereof, and to their production : wherein R¹ represents a lower acyl group; R² represents a lower alkyl group; A represents a lower alkylene group which may be hydroxy-substituted; Y represents an oxygen atom, a sulfur atom, a carbonylimino group (-CONH-), or an iminocarbonyl group (-NHCO-); represents a 5- or 6-membered heterocyclic ring which has 1 to 3 hetero atoms selected from oxygen sulfur and nitrogen,is bonded directly to Y, and may be fused with a benzene ring; and R³, R⁴ and R⁵, each of which may be present or absent, are the same or different and selected from lower alkyl groups, groups of formula -A¹-R⁶ [wherein A¹ represents a lower alkylene group and R⁶ represents a hydroxy group, a mercapto group, a carboxy group, or a(lower alkoxy)carbonyl group], a hydroxy group, a mercapto group, lower alkoxy groups, lower alkylthio groups, groups of formula -Y¹-A²-R⁷ [wherein Y¹ represents an oxygen atom or a sulfur atom, A² represents a lower alkylene group, and R⁷ represents a carboxy group, a (lower alkoxy)-carbonyl group, a hydroxyaminocarbonyl group, a mono- or a di-(lower alkyl)aminocarbonyl group, or an N-(lower alkyl)hydroxyaminocarbonyl group] an oxo group (=O), a thioxo group (=S), an amino group, groups of formula -NH-R⁸ [wherein R⁸ represents a carboxy lower alkyl group or a(lower alkoxy)carbonyl (lower alkyl) group], groups of formula -NH-CO-R⁹ [wherein R⁹ represents a carboxy(lower alkyl)group, a (lower alkoxy)carbonyl (lower alkyl)group, a (lower alkoxy)phenyl(lower alkoxy) carbonyl (lower alkyl) group, a carboxy group, or a (lower alkoxy)carbonyl group], a carboxy group, or groups of formula -CO-R¹⁰ [wherein R¹⁰ represents a lower alkoxy group]. It is generally considered that in allergic asthma and other atopic diseases of man or anaphylactic shock in animals, various chemical mediators are released from the lung and other tissues and cause problems such as the constriction of smooth muscles, e.g., bronchi, pulmonary artery, etc., and the enahncement of vascular permeability in the skin. As such chemical mediators, there are histamine and SRS-A. Histamine plays an important role in guinea pig anaphylactic shock but not in allergic asthma in man (Eiser, "Pharmacology and Therapeutics", 17 , 239-250 (1982)), whereas some evidence suggests that SRS-A is the most important chemical mediator of allergic asthma in man (Brocklehurst, "Journal of Physiology", 151 , 416-435(1960); Austen and Orange, "American Review of Respiratory Diseases", 12 , 423-436(1975); Adams and Lichtenstein, "Journal of Immunology", 122 , 555-562(1979)). The development of medicaments for prophylaxis, elimination and reduction of immediate hypersensitivity reactions has aimed at inhibiting the production and release of such chemical mediators or antagonizing the action of these chamical mediators. As an inhibitor of histamine release, disodium cromoglycate is well known and as an inhibitor of actions induced by histamine, various anti-histaminics are commercially available. SRS-A is known as a slowly reactive and long acting chemical mediator while histamine is a rapid acting and short acting chemical mediator, and it has recently been recognized that SRS-A is a mixture of Leukotriens C₄, D₄ and E₄ the structure of which have been clarified by Dr. Samuelsson. SRS-A, i.e., Leukotriens are lipoxigenase products of polyunsaturated fatty acids (in particular, arachidonic acid) and it has been reported that SRS-A has various activities such as enhancment of mucus production, reduction of mucociliary transport, coronary artery constrictor action, reduction of cardiac contractibility, etc., besides the aforesaid action as chemical mediator in immediate hypersensitivity reactions. To delineate the dynamic roles of SRS-A and to modulate its actions in various pathological conditions, obviously it would be highly desirable to have a specific and in vivo active receptor antagonist. Furthermore, it is clinically desirable to prepare an orally active compound. FPL 55712* of Fisons shows potent anti-SRS-A activity in isolated tissues (Augstein et al, Nature New Biol., 245 , 215-217(1973)). However, its biological hale life is very short and its absorption by the oral route is very poor (Sheard et al, Mongr. Allergy, 12 , 245-249(1977)). We have found that the compounds shown by general formula (I) described above and the salts thereof strongly antagonize the actions of SRS-A, are effective in oral administration, and show very weak toxicity. The compounds of this invention have the structural characteristic that the 5- or 6-membered heterocyclic ring (c) having 1 to 3 hetero atoms is directly bonded to moiety (b) : Related known compounds are e.g. above-described FPL 55712 of Fisons, and those of UK Patent No.2,058,785 which have the general formula In these compounds, moiety (c) is a benzene ring or a benzene ring with which a heterocyclic ring is condensed and in each case the benzene ring is directly bonded to moiety (b). The only known instance of such compounds wherein the moiety (c) is a heterocyclic ring is that where it is a tetrazole (Japanese Patent Publication No.104,344/84, EP-A-0108592). The term "lower" in this specification means a straight or branched carbon chain of 1 to 6 carbon atoms. Accordingly, the lower alkyl groups herein include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 1,2-dimethylpropyl group, a hexyl group, an isohexyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, a 1,1-dimethylbutyl group, a 1,2-dimethylbutyl group, a 2,2-dimethylbutyl group, a 1,3-dimethylbutyl group, a 2,3-dimethylbutyl group, a 3,3-dimethylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 1,1,2-trimethylpropyl group, a 1,2,2-trimethylpropyl group, a 1-ethyl-1-methylpropyl group, a 1-ethyl-2-methylpropyl group, etc. Also, the lower acyl groups include a formyl group, an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, a valeryl group, an isovaleryl group, a pivaloyl group, a hexanoyl group, etc. Furthermore, the lower alkylene groups include straight chain and branched alkylene groups having 1 to 6 carbon atoms, such as a methylene group, an ethylene group, a methylmethylene group a trimethylene group, a 1-methylethylene group a 2-methylethylene group a tetramethylene group, a 1-methyltrimethylene group, a 2-methyltrimethylene group, a 3-methyltrimethylene group, a 1-ethylethylene group, a 2-ethylethylene group, a pentamethylene group, a 1-methyltetramethylene group, a 2-methyltetramethylene group, a 3-methyltetramethylene group, a 4-methyltetramethylene group, a hexamethylene group, etc. Practical examples of the hydroxy-substituted lower alkylene groups are those in which a hydrogen atom at an optional position of an above-described lower alkylene group is substituted by a hydroxy group, such as a hydroxymethylene group, a 1-hydroxyethylene group, a 2-hydroxyethylene group, a 1-hydroxytrimethylene group, a 2-hydroxytrimethylene group, a 3-hydroxytrimethylene group, a 1-hydroxy-2-methylethylene group, a 2-hydroxy-1-methylethylene group, a 1-hydroxytetramethylene group, a 2-hydroxytetramethylene group, a 3-hydroxytetramethylene group, a 4-hydroxytetramethylene group, a 2-hydroxy-1-methyltrimethylene group, a 2-hydroxy-3-methyltetramethylene group, a 2-hydroxypentamethylene group, a 4-hydroxypentamethylene group, a 2-hydroxyhexamethylene group, a 5-hydroxyhexamethylene group, etc. Also, the lower alkoxy groups herein include straight chain and branched alkoxy groups having 1 to 6 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, an isopentyloxy group, a neopentyloxy group, a tert-pentyloxy group, a hexyloxy group, etc. The lower alkylthio groups are straight chain or branched alkylthio groups having 1 to 6 carbon atoms and include a methylthio group, an ethylthio group, a propylthio group, an isopropylthio group, a butylthio group, an isobutylthio group, a sec-butylthio group, a tert-butylthio group, a pentylthio group, an isopentylthio group, a neopentylthio group, a tertpentylthio group, a hexylthio group, etc. The lower alkoxycarbonyl groups have straight or branched chains of 1 to 6 carbon atoms and a carboxy group and include a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, an isopropoxycarbonyl group, a butoxycarbonyl group, an isobutoxycarbonyl group, a sec-butoxycarbonyl group, a tertbutoxycarbonyl group, a pentyloxycarbonyl group, an isopentyloxycarbonyl group, a neopentyloxycarbonyl group, a tert-pentyloxycarbonyl group, a hexyloxycarbonyl group, etc. Also, the term "mono- or di-lower alkylamino-carbonyl group" means an aminocarbonyl group with one or two hydrogen atoms substituted by above-described lower alkyl group(s); examples are an aminocarbonyl group mono-substituted by a straight chain or branched alkyl group having 1 to 6 carbon atoms, such as a methylaminocarbonyl group, an ethylaminocarbonyl group, a propylaminocarbonyl group, an isopropylaminocarbonyl group, a butylaminocarbanoyl group, an isobutylaminocarbonyl group, a pentylaminocarbonyl group, an isopentylaminocarbonyl group, a hexylaminocarbonyl group, etc.; an aminocarbonyl group symmetrically di-substituted by a straight chain or branched alkyl group having 1 to 6 carbon atoms, such as a dimethylaminocarbonyl group, a diethylaminocarbonyl group, a dipropylaminocarbonyl group, a diisopropylaminocarbonyl group, a dibutylaminocarbonyl group, a dipentylaminocarbonyl gorup, a dihexylaminocarbonyl group, etc.; and an aminocarbonyl group asymmetrically di-substituted by different alkyl groups each having 1 to 6 carbon atoms, such as an ethylmethylaminocarbonyl group, a methylpropylaminocarbonyl group, an ethylpropylaminocarbonyl group, a butylmethylaminocarbonyl group, a butylethylaminocarbonyl group, a butylpropylaminocarbonyl group, etc. The term "N-(lower alkyl)hydroxyaminocarbonyl group" means a hydroxyaminocarbonyl group in which the hydrogen atom bonded to the nitrogen atom is substituted by an above-described lower alkyl group. Practical examples thereof are an N-methylhydroxyaminocarbonyl group, an N-ethylhydroxyaminocarbonyl group, an N-propylhydroxyaminocarbonyl group, an N-isopropylhydroxyaminocarbonyl group, an N-butylhydroxyaminocarbonyl group, an N-isobutylhydroxyaminocarbonyl group, an N-pentylhydroxycarbonyl group, an N-isopentylhydroxyaminocarbonyl group, an N-hexylhydroxyaminocarbonyl group, etc. The terms "carboxy lower alkyl group","(lower alkoxy)carbonyl (lower alkyl) group", and "(lower alkoxy)phenyl (lower alkoxy)carbonyl(lower alkyl)group" mean an aforesaid lower alkyl group an optional hydrogen atom of which is substituted by the "carboxy group","(lower alkoxy)carbonyl group" or "(lower alkoxy)phenyl (lower alkoxy)carbonyl group", respectively. In addition, the "(lower alkoxy)phenyl(lower alkoxy)carbonyl group" means an aforesaid "(lower alkoxy)carbonyl group" an optional hydrogen atom of which is substituted by a phenyl group having an above-described lower alkoxy group at the ortho-, meta- or para-position. Preferred examples of the 5- or 6-membered heterocyclic ring having 1 to 3 hetero atoms selected from an oxygen atom, a sulfur atom, and a nitrogen atom shown by are a 1,3-thiazole ring a 4,5-dihydro-1,3-thiazole ring an isothiazole ring a 1,2,3-thiadiazole ring a 1,2,4-thiadiazole ring a 1,3-oxazole ring a 4,5-dihdyroxazole ring an isoxazole ring a 1,3,4-oxadiazole ring an imidazole ring a pyrazole ring a 1H-1,2,3-triazole ring a 1H-1,2,4-triazole ring a 2H-pyran ring a 4H-pyran ring a pyrimidine ring etc. Examples of the condensates of these heterocyclic rings and a benzene ring are a benzothiazole ring a benzimidazole ring etc. When the heterocyclic ring is fused with a benzene ring, R³, R⁴, and R⁵ above indicate groups bonded directly to the heterocyclic ring - though one, two or all three may be absent just as in the cases where Het is a heterocyclic ring alone. In the case of some fused rings, according to the heterocyclic moiety, at least one R³, R⁴ and R⁵ is inevitably absent. Examples of R³, R⁴, and R⁵ on the heterocyclic ring are lower alkyl groups; hydroxy-, mercapto-, carboxy- and (lower alkoxy)carbonyl-substituted lower alkylene groups of formula -A¹-R⁶; -OH; -SH; lower alkoxy groups; lower alkylthio groups; carboxy-, (lower alkoxy)carbonyl-, mono- or di-(lower alkyl)aminocarbonyl-, hydroxyaminocarbonyl-, and N-(lower alkyl)hydroxyaminocarbonyl-substituted lower alkoxy and lower alkylthio groups of formula -Y¹-A²-R⁷; an oxo group; a thioxo group; an amino group; carboxy- and (lower alkoxy)carbonyl-substituted lower alkylamino groups of formula -NH-R⁸; carboxy (lower alkanoyl)amino groups; (lower alkoxy)carbonyl (lower alkanoyl)amino groups; (lower alkoxy)phenyl (lower alkoxy)carbonyl (lower alkanoyl)amino groups; oxaloamino and (lower alkoxy)oxalylamino groups of formula -NH-CO-R⁹; a carboxy group; and (lower alkoxy)carbonyl groups of formula -CO-R¹⁰. The "lower alkanoyl group" of the above-described carboxy (lower alkanoyl)amino, (lower alkoxy)carbonyl (lower alkanoyl)amino, and (lower alkoxy)phenyl (lower alokoxy)carbonyl (lower alkanoyl)amino groups is a straight chain or branched alkylcarbonyl group having 2 to 6 carbon atoms, such as an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, a valeryl group, an isovaleryl group, a pivaloyl group, a hexanoyl group, etc. The compounds of this invention include optical isomers based on the existence of asymmetric carbon; tautomers based on the kind of heterocyclic ring or the presence of an oxo group, a hydroxy group, a thioxo group or a mercapto group; and cis-trans geometrical isomers based on two different substituents bonded to the saturated or partially saturated heterocyclic ring. This invention includes all such isomers, individually and in any admixture of two or more thereof. Some of the compounds of this invention form salts and the invention includes these salts. Examples of such salts are those with inorganic base such as sodium, potassium, etc.; those with organic base such as ethylamine, propylamine, diethylamine, triethylamine, morpholin, piperidine, N-ethylpiperidine, diethanolamine, cyclohexylamine, etc.; those with basic amino acid such as lysine, ornithine, etc.; the ammonium salts; salts with mineral acid such as hydrochloric acid, sulfuric acid, phosphoric acid, hydrobromic acid, etc.; salts with organic acid such as acetic acid, oxalic acid, succinic acid, citric acid, maleic acid, malic acid, fumaric acid, tartaric acid, methansulfonic acid, etc.; and salts with acidic amino acid such as glutamic acid, aspartic acid, etc. The compounds of this invention shown by general formula (I) can be prepared by various processes. Typical production process of the compounds are illustrated below : In the above formulae, R¹, R², A, Y, R³, R⁴, R⁵, Y¹, A², R⁷, and R⁹ have the same significance as defined above and other symbols have the following meanings: X: A halogen atom. M: A hydrogen atom or an alkali metal atom. Y²: An oxygen atom or a sulfur atom. R¹¹: A hydrogen atom or a lower alkyl group. R¹²: A lower alkyl group or a hydroxy group. Y³: A single bond, an oxygen atom, a sulfur atom, or an imino group (-NH-). R¹³: A lower alkyl group. A³: A single bond, a lower alkylene group or, when Y³ is an imino group; a carbonyl group or a carbonyl lower alkylene group. A⁴: A single bond or a lower alkylene group having 1 to 4 carbon atoms. R 3' , R 4' , and R 5' : each present or absent, the same or different and each may be a lower alkyl group, -A¹-R 6' (wherein A¹ is as defined above and R 6' is a hydroxy group, a carboxy group, or a (lower alkoxy)carbonyl group), a hydroxy group, a lower alkoxy group, a lower alkylthio group, -Y¹-A²-R 7' (wherein Y¹ and A² are as defined above and R 7' represents a (lower alkoxy)carbonyl group, a hydroxyaminocarbonyl group, a mono- or di-(lower alkyl)aminocarbonyl group, or an N-(lower alkyl)hydroxyaminocarbonyl group), an oxo group (=O), an amino group, -NH-R 8' (wherein R 8' represents a(lower alkoxy)carbonyl group), -NH-CO-R 9' (wherein R 9' represents a(lower alkoxy)carbonyl (lower alkyl) group, a (lower alkoxy)phenyl (lower alkoxy)carbonyl (lower alkyl) group, or a(lower alkoxy)carbonyl group), a carboxy group, or -CO-R¹⁰ (wherein, R¹⁰ is as defined above). R 3'' , R 4'' , and R 5'' : each present or absent, the same or different, and each may be a lower alkyl group, -A¹-R 6'' (wherein A¹ is as defined above and R 6'' represents a hydroxy group, a carboxy group, or a (lower alkoxy)carbonyl group), a hydroxy group, a lower alkoxy group, a lower alkylthio group, -Y¹-A²-R⁷ (wherein Y¹, A², and R⁷ are as defined above), an oxo group (=O), an amino group, -NH-R⁸ (wherein R⁸ is as defined above), -NH-CO-R⁹ (wherein R⁹ is as defined above), a carboxy group, or -CO-R¹⁰ (wherein R¹⁰ is as defined above). A halogen atom can be a iodine atom, a bromine atom, a chlorine atom, etc., and an alkali metal atom can be sodium, potassium, etc. Process A: A compound of this invention wherein Y is an oxygen atom or a sulfur atom is produced by reacting a halogen compound (II) and a hydroxy compound or mercapto compound (III), or an alkali metal substitution product thereof. The reaction can be performed using the compounds (II) and (III in almost equimolar amounts, or with a slight excess of one, in an organic solvent such as dimethylformamide, dimethylsulphofoxide, methanol, ethanol, propanol, acetone, methyl ethyl ketone, tetrahydrofuran, chloroform, dioxane, etc., water, or a mixed solvent thereof. When a hydroxy- or mercapto-substituted heterocyclic compound is used as the compound (III), reaction is usually in the presence of base and suitable examples of such a base are potassium carbonate, Triton B, potassium hydroxide, sodium hydroxide, sodium hydride, etc. There is no particular restriction on the reaction temperature but the reaction is usually performed at room temperature or under heating. Process B: A compound (Ib) which is a compound (I) of this invention wherein Y is a carbonylimino group (-CONH-) is produced by reacting carboxylic acid (IV) or reactive derivative thereof and amino compound (V). As reactive derivatives of compound (IV), there are acid halides such as acid chloride, acid bromide, etc.; acid azides, active esters prepared with N-hydroxybenzotriazole or N-hydroxysuccinimide; symmetric acid anhydrides; mixed acid anhydrides prepared with alkyl chlorocarbonate or p-toluenesulfonyl chloride; etc. When compound (IV) is used as a free carboxylic acid, it is advantageous to perform the reaction in the presence of a condensing agent such as dicyclohexylcarbodiimide, 1,1'-carbonyldiimidazole, etc. The reaction can be performed using the compound (IV) or reactive derivative thereof and compound (V) in almost equimolar amounts, or with slight excess of one, in an organic solvent inactive to the reaction, such as pyridine, tetrahydrofuran, dioxane, ether, benzene, toluene, xylene, methylene chloride, dichloroethane, chloroform, dimethylformamide, ethyl acetate, acetonitrile, etc. According to the kind of the reactive derivative, it is sometimes advantageous for smooth reaction to add a base such as triethylamine, pyridine, picoline, lutidine, N,N-dimethylaniline, potassium carbonate, sodium hydroxide, etc. Pyridine can be also used as the solvent. The reaction temperature depends upon the kind of reactive derivative and is not critical. Process C: A compound (Ic), which is a compound (I) of this invention (I) wherein Y is an iminocarbonyl group (-NHCO-) is produced by reacting amine (VI) and carboxylic acid (VII). The reaction conditions, etc., are as in Process B. Process D: A compound (Id) wherein the heterocyclic ring is substituted by a lower alkoxy group, a lower alkylthio group, a (lower alkoxy)carbonyl lower alkoxy group, a lower(alkoxy)carbonyl lower alkylthio group, a carboxy lower alkoxy group, a carboxy lower alkylthio group, a (lower alkoxy)carbonyl lower alkoxy group, or a (lower alkoxy)carbonyl lower alkylthio group can be produced by reacting compound VIII of this invention wherein the heterocyclic ring is substituted by a hydroxy group or a mercapto group, or alkali metal substitution product thereof, and halogen compound (IX). The reaction can be performed almost as in Process A. When a compound (VIII) whose heterocyclic ring has a plurality of -Y¹-M substituents is used as raw material, it is possible to prepare a product having a corresponding number of -Y¹-A²-R⁷ substituents. Process E: A compound of this invention wherein the heterocyclic ring is substituted by a carboxy lower alkanoylamino group, a (lower alkoxy)carbonyl lower alkanoylamino group, a (lower alkoxy)phenyl (lower alkoxy)carbonyl lower alkanoylamino group, an oxaloamino group or a(lower alkoxy)oxalylamino group can be produced by reacting compound (Ie),wherein the heterocyclic ring is substituted by an amino group, with carboxylic acid (X) or reactive derivative thereof. The reaction conditions, etc., are almost as in Processes B and C. When a compound whose heterocyclic ring has plural amino groups is used as the raw material, a product wherein all the amino groups are reacted can be obtained. Process F: A compound of this invention wherein the heterocyclic ring is substituted by a mono- or di-(lower alkyl)aminocarbonyl lower alkoxy group, a mono- or di-(lower alkyl)aminocarbonyl lower alkylthio group, an (N-lower alkyl)hydroxyaminocarbonyl lower alkoxy group, or an (N-lower alkyl)hydroxyaminocarbonyl lower alkylthio group is produced by reacting carboxylic acid (Ig) or reactive derivative thereof and amine (XI). The reaction is performed in the same way as Processes B, C and E. When a compound whose heterocyclic ring has plural carboxy groups is used as raw material, a product wherein the carboxy groups are wholly or selectively reacted can be obtained. Process G: A free carboxylic acid compound (Ij) can be easily produced by hydrolysis of corresponding ester compound (Ii). In the reaction, a conventional hydrolysis in the presence of base such as sodium carbonate, sodium hydroxide, etc., or acid such as trifluoroacetic acid, hydrochloric acid, etc., can be applied. When a compound whose heterocyclic ring has plural esters is used as the raw material, a product wherein all the esters are hydrolyzed may be obtained. Process H: A compound (Ik) having no free mercapto group, carboxy group or reactive hydroxy group is produced by reacting dihydroxybenzene derivative (XII) or alkali metal substitution product thereof, with halogen compound (XIII). The reaction can be performed as in Processes A and D wherein, in particular, compound in which Y¹ or Y² is an oxygen atom is used. Process I: A compound of this invention wherein A is a 2-hydroxy lower alkylene group can be produced by reacting epoxy compound (XIV) and hydroxy or mercapto compound (having no other mercapto group) or alkali metal substitution product thereof. The reaction can be substantially as in Processes A, D, and H, i.e. using the compounds (XIV) and (XV) in almost equimolar amounts,or with excess of one, in an organic solvent inactive to the reaction, such as dimethylformamide, dimethylsulfoxide, methanol, ethanol, propanol, acetone, ethyl methyl ketone, tetrahydrofuran, chloroform, dioxane, etc. When a free hydroxy compound or mercapto compound is used as compound (XV), the reaction is performed in the presence of a base such as potassium carbonate, Triton B, potassium hydroxide, sodium hydroxide, sodium hydride, etc., preferably under water-free conditions. Process J: Contrary to the case of Process G, ester compound (Ii) is synthesized by reacting carboxylic acid (Ij) or reactive derivative thereof with lower alcohol (XVI) or reactive derivative thereof (such as a lower alkyl halide, etc.). The reaction can be accomplished easily in conventional manner. The compounds of this invention produced by the various processes described above can be isolated and purified by conventional operations such as extraction, recrystallization, column chromatography, etc. The compounds of this invention strongly antagonize the actions of SRS-A as described hereinbefore and hence are useful for the prophylaxis and treatment of various allergic diseases (e.g., bronchial asthma, allergic rhinitis, urticaria, etc.), ischemic heart diseases and ischemic brain diseases, inflamations, etc., caused by SRS-A. At least some compounds of this invention also inhibit the production and release of SRS-A and have bronchodilator action. Compounds of this invention may also be useful as anti-ulcer agents. Inhibition of SRS-A- and LTD₄-induced contraction of guinea pig ileum and trachea Method: Male Hartley guinea-pigs weighing 500 to 700 g were killed by a blow on the head. The ileum and tracheal strips prepared according to the method of Constantine (1965) were suspended with 1.0 g tension in an organ bath containing 10 ml of Tyrode solution equilibrated with a mixture of 95% O₂ and 5% CO₂ at 37°C. The tissues were equilibrated for 60 min.; during this period the Tyrode solution was replaced every 15 min. and the loading tension was adjusted to 1.0 g. The developed tension of the tissues was measured isometrically with a strain gauge transducer, and recorded on a Recticorder. Both the contractile response of the ileum to submaximal concentration of SRS-A (derived from guinea-pig lung) and the tracheal response to 10⁻⁸M LTD₄ were measured in the absence and then the presence of various concentrations of test compounds. The incubation time of the compounds was 20 min. Example No. Anti-SRS-A GP ileum IC50(M) Example No. Anti-SRS-A GP ileum IC50(M) 2 1.8x10⁻⁷ 36 1.4x10⁻⁷ 7 1.1x10⁻⁷ 37 5.2x10⁻⁸ 21 6.0x10⁻⁸ 38 3.8x10⁻⁸ 23 1.5x10⁻⁷ 41 6.4x10⁻⁸ 24 1.9x10⁻⁷ 42 1.3x10⁻⁷ 26 1.2x10⁻⁷ 44 1.3x10⁻⁷ 27 1.9x10⁻⁷ 46 1.1x10⁻⁷ 33 9.1x10⁻⁸ 51 1.6x10⁻⁷ Example No. Anti-LTD₄ GP trachea IC50(M) 21 1.3x10⁻⁷ 38 2.3x10⁻⁷ 51 4.2x10⁻⁷ Inhibition of SRS-A-mediated anaphylactic asthma in conscious guinea-pigs Method: Male Hartley guinea-pigs weighing 370 to 410 g were passively sensitized by intravenously injecting 1 ml/kg of rabbit anti-bovine serum albumin serum (PHA titer: 20480). Twenty-four hours after the sensitization, indomethacine (2 mg/kg), mepyramine (2 mg/kg) and propranolol (0.3 mg/kg) were injected into the saphenous vein 20, 5 and 5 min., respectively, prior to the antigen challenge. Then, animals were placed in an 11 liter chamber connected to a glass nebulizer, and 1% solution of bovin serum albumin was sprayed into the chamber for 30 seconds. The animals were exposed to the antigen aerosol for 2 min. and observed for 15 min. after challenge. The time from the start of inhalation to the onset of cough and the mortality were recorded. Test compounds were orally administered 30 min. before antigen challenge. Result: Compound of Example 21 at 3 mg/kg p.o. tended to inhibit the SRS-A-mediated anaphylactic asthma in conscious guinea-pigs, but this effect was not significant (Table 3). At doses of 10 mg/kg p.o. or higher, compound of Example 21 significantly inhibited the SRS-A-mediated anaphylactic asthma. Effect of Compound of Example 21 on SRS-A-mediated anaphylactic asthma in conscious guinea-pigs Compound Dose (mg/kg p.o.) N Time to onset of cough (sec) Mortality Control - 8 293 ± 22 6/8 Compound 3 8 377 ± 51 5/8 Control - 8 281 ± 19 2/8 Compound 10 8 397 ± 42 2/8 Control - 8 281 ± 11 7/8 Compound 30 8 457 ± 42 2/8 Toxicity The minimum fatal dose of orally administered compound of Example 21 for mice and rats was more than 1000 mg/kg in each case. The compounds of this invention can be orally or parenterally administered as they are or as medical compositions of these compounds and pharmaceutically permissible carriers or excipients (e.g., tablets, capsules, powders, granules, pills, ointments, syrups, injections, inhalants, suppositories, etc.). The dose depends upon the patient, administration route, symptoms, etc., but is usually 0.1 to 500 mg, preferably 1 to 200 mg,per adult per day orally or parenterally administered 2 or 3 times per day. The invention is illustrated by the following Examples. In addition, the production of starting compounds used in these Examples is shown in the following Peference Examples, wherein nPr means an n-propyl group. Reference Example 1 After stirring a mixture of 60 g of 2,5-dimercapto-1,3,4-thiadiazole, 25 g of potassium hydroxide, and 750 ml of ethanol for one hour at 70°C, 68 g of ethyl α-bromoacetate was added to the mixture and then the resultant mixture was refluxed for 2 hours. After cooling the reaction mixture, insoluble matters were filtered off and the filtrate thus formed was concentrated under reduced pressure. To the residue thus formed was added 600 ml of 10% sodium hydroxide. The mixture was stirred for one hour at 80°C. After cooling, the reaction mixture was acidified by the addition of concentrated hydrochloric acid (below pH 1) and crystals thus formed were collected by filtration, washed with water, and recrystallized from acetone to provide 60 g of [(5-mercapto-1,3,4-thiadiazol-2-yl)thio]acetic acid. Melting point: 170°C. Reference Example 2 To a mixture of 3 g of 2,5-dimercapto-1,3,4-thiadiazole, 2.76 g of anhydrous potassium carbonate, and 10 ml of N,N-dimethylformamide was added 1 g of ethyl 4-bromobutyrate and the mixture was stirred overnight at room temperature. After addition of dilute hydrochloric acid to the reaction mixture, the product was extracted with ethyl acetate. The extract was washed with water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue thus obtained was subjected to silica gel chromatography (using 200 ml of silica gel) and eluted with a mixture of toluene and ethyl acetate (9 : 1) to provide 0.95 g of ethyl 4-[(5-mercapto-1,3,4-thiadiazol-2-yl)thio]butyrate. Melting point: 107 to 108°C Reference Example 3 A mixture of 1.42 g of 2,4-dihydroxy-3-propylacetophenone, 2 g of ethyl 4-bromobutyrate, 1.5 g of potassium carbonate, and 10 ml of N,N-dimethylformamide was stirred overnight at room temperature. After addition of 100 ml of water to the reaction mixture, the product was extracted with 30 ml of toluene. The extract was washed with water, dried over anhydrous magnesium sulfate, and solvent was distilled off. The residue thus formed was subjected to silica gel column chromatography and eluted with toluene to provide 1.5 g of ethyl 4-(4-acetyl-3-hydroxy-2-propylphenoxy)butyrate as an oily product. In a solution of 2 g of potassium hydroxide in 4O ml of 8O% methanol was dissolved 1.3 g of the oily product and the solution was allowed to stand for one hour. To the reaction mixture was added 20 ml of water and methanol was distilled off under reduced pressure. The aqueous solution thus obtained was acidified by 5% hydrochloric acid and extracted by ethyl acetate. The extract thus formed was washed with water and dried over anhydrous magnesium sulfate. The solvent was distilled off to provide 1.1 g of 4-(4-acetyl-3-hydroxy-2-propylphenoxy)-butyric acid. Melting point: 138 to 139°C. Reference Example 4 In a mixture of 9.66 g of sodium hydroxide, 14.6 ml of water, and 122 ml of methanol was dissolved 36.3 g of 2,5-dimercapto-1,3,4-thiadiazole. After cooling the mixture, a solution of 24.1 ml of ethyl bromoacetate and 24 ml of methanol was added to the mixture below 10°C. The resultant mixture was stirred for 3 hours at room temperature and cooled below 10°C. 43.5 ml of water and 400 ml of 50% methanol were successively added to the reaction mixture, whereby crystals precipitated, and the mixture was allowed to stand overnight at 4°C. The crystals were collected by filtration, washed successively with water and then 50% methanol, and dried to provide 42.5 g of ethyl [(5-mercapto-1,3,4-thiadiazol-2-yl)thio]acetate. Melting point: 67 to 68°C Reference Example 5 To a mixture of 10 g of 2,5-dimercapto-1,3,4-thiadiazole and 100 ml of methanol were added 2.6 g of sodium-hydroxide and 5 ml of water. To the mixture was gradually added 9 g of ethyl 5-bromovalerate. The resultant mixture was stirred for one hour at room temperature. The reaction mixture thus obtained was concentrated under reduced pressure. After addition of 100 ml of water the product was extracted with ethyl acetate. The extract thus formed was washed with water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was subjected to silica gel gel column chromatography and eluted with a mixture of toluene and ethyl acetate (9 : 1) to provide 10 g of ethyl 5-[(5-mercapto-1,3,4-thiadiazol-2-yl)thio]valerate. Melting point: 53°C. Reference Example 6 To a mixture of 7.6 g of 2,5-dimercapto-1,3,4-thiadiazole, 1.5 ml of water, 15 ml of methanol, and 2.0 g of sodium hydroxide was added 7.4 g of ethyl 6-bromohexanoate and the mixture was stirred for 2 hours at room temperature. After acidification of the resulting reaction mixture with dilute hydrochloric acid, 150 ml of water was added thereto. The mixture was extracted with toluene and the extract thus formed was washed with water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue thus formed was recrystallized from a mixture of toluene and n-hexane to provide ethyl 6-[(5-mercapto-1,3,4-thiadiazol-2-yl)thio]hexanoate. Melting point: 79 to 80°C. Reference Example 7 By following the same procedure as Reference Example 6 using 6.9 g of 2,5-dimercapto-1,3,4-thiadiazole and 5.8 g of ethyl 4-chlorovalerate as the starting materials, 1.5 g of ethyl 4-[(5-mercapto-1,3,4-thiadiazol-2-yl)thio]valerate was obtained as an oily product. Nuclear magnetic resonance spectra (CDCl₃, TMS internal standard, ppm) 1.25(t, 3H), 1.45(d, 3H), 2.08(t, 2H), 2.52(t, 2H), 3.70(q, 1H), 4.15(q, 2H) Reference Example 8 By following the same procedure as Reference Example 6 using 7.5 g of 2,5-dimercapto-1,3,4-thiadiazole and 5.8 g of ethyl 2-bromopropionate as the starting materials, 6.1 g of ethyl 2-[(5-mercapto-1,3,4-thiadiazol-2-yl)thio]propionate was obtained as an oily product. Nuclear magnetic resonance spectra (CDCl₃, TMS internal standard, ppm) 1.28(t, 3H), 1.64(d, 3H), 4.0-4.80(m, 3H) Reference Example 9 To a mixture of 1.5 g of 2,5-dimercapto-1,3,4-thiadiazole, 1.3 g of anhydrous potassium carbonate, and 20 ml of N,N-dimethylformamide was added 1.6 g of 3-bromopropionic acid, whereby the red color of the reaction mixture began to gradually fade and the reaction mixture became yellow. Then, the reaction mixture was poured into 100 ml of ice water and extracted with 30 ml of ethyl acetate three times. The extract thus obtained was washed with water and extracted with 20 ml of an aqueous solution of 5% sodium hydrogen carbonate two times. The extract was washed with ethyl acetate, acidified with dilute hydrochloric acid, and extracted with 30 ml of ethyl acetate three times and the extract thus obtained was washed with water, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to provide 0.76 g of 3-[(5-mercapto-1,3,4-thiadiazol-2-yl)thio]propionic acid. Melting point: 105 to 108°C. Reference Example 10 A mixture of 3 g of 2,4-dihydroxy-3-propylacetophenone, 2.5 g of ethyl bromoacetate, 2.3 g of anhydrous potassium carbonate, and 30 ml of methyl ethyl ketone was refluxed for 5 hours. Then, the solvent was removed under reduced pressure and after addition of 50 ml of toluene, the mixture was washed successively with water, dilute aqueous sodium hydroxide, and water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue thus formed was recrystallized from a mixture of toluene and n-hexane to provide 2.8 g of ethyl (4-acetyl-3-hydroxy-2-propylphenoxy)acetate (melting point; 66 to 66.5°C). A mixture of the product thus obtained, 20 ml of methanol, and 8 ml of a 2N aqueous solution of sodium hydroxide was stirred for 2 hours at 50°C. Then, the reaction mixture thus obtained was concentrated under reduced pressure, mixed with 30 ml of water, and washed with toluene. The aqueous layer was acidified with dilute hydrochloric acid and extracted with ethyl acetate. The extract thus formed was washed with water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue thus formed was recrystallized from isopropanol to provide 2.3 g of (4-acetyl-3-hydroxy-2-propylphenoxy)acetic acid. Melting point: 140 to 141°C. Reference Exmaple 11 A mixture of 1 g of 2,4-dihydroxy-3-propylacetophenone, 1.1 g of 1-bromo-2-chloroethane, 0.75 g of anhydrous potassium carbonate, and 0.05 g of tetra-n-butylammonium bromide was refluxed for 3 hours with vigorous stirring. After cooling, 30 ml of toluene was added to the reaction mixture and the mixture was washed with a dilute aqueous solution of sodium hydroxide, washed with water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue thus formed was recrystallized from isopropanol to provide 0.46 g of 4-(2-chloroethoxy)-2-hydroxy-3-propylacetophenone. Melting point: 73 to 74°C Elemental analysis for C₁₃H₁₇O₃Cl: C H Cl Calculated: 60.82% 6.67% 13.81% Found: 60.67% 6.72% 13.76% Reference Example 12 By following the same procedure as Reference Example 11 using 1 g of 2,4-dihydroxy-3-propylacetophenone and 4.5 g of 1,4-dibromobutane as starting materials followed by purification by silica gel column chromatography (Eluent: toluene), 1.3 g of 4-(4-bromobutoxy)-2-hydroxy-3-propylacetophenone was obtained as an oily product. Nuclear magnetic resonance spectra (CDCl₃, TMS internal standard, ppm) 0.95(t, 3H), 1.10-1.80(m, 2H), 1.80-2.20(m, 4H), 2,58(s, 3H), 2,64(t, 2H), 3,52(t, 2H), 4,08(t, 2H), 6.42(d, 1H), 7.58(d, 1H), 12.7(s, 1H). Reference Example 13 By following the same procedure as Reference Example 11 using 1 g of 2,4-dihydroxy-3-propylacetophenone and 4.7 g of 1,5-dibromopentane as the raw materials, 1.3 g of 4-(5-bromopentyloxy)-2-hydroxy-3-propylacetophenone was obtained as an oily product. Nuclear magnetic resonance spectra (CDCl₃, TMS internal standard, ppm) 0.94(t, 3H), 1.30-2.10(m, 8H), 2.56(s, 3H), 2.64(t, 2H), 3,46(t, 2H), 4,40(t, 2H), 6,42(d, 1H), 7.58(d, 1H), 12.72(s, 1H). Reference Example 14 A mixture of 3 g of ethyl [(5-mercapto-1,3,4-thiadiazol-2-yl)thio]acetate, 9 g of 1,3-dibromopropane, 2.02 g of anhydrous potassium carbonate, 0.01 g of tetra-n-butylammonium bromide, and 20 ml of methyl ethyl ketone was vigorously stirred for 3 hours at 60°C Toluene was added to the reaction mixture and the resultant mixture was washed with water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue thus formed was subjected to silica gel column chromatography and eluted with a mixture of toluene and ethyl acetate (9 : 1) to provide 1.35 g of ethyl [[5-(3-bromopropyl)thio-1,3,4-thiadiazol-2-yl]thio]acetate. Melting point: 118 to 120°C. Example 1 To a mixture of 600 mg of 2,5-dimercapto-1,3,4-thiadiazole, 560 mg of anhydrous potassium carbonate, and 10 ml of N,N-dimethylformamide was added 250 mg of 4-(2,3-epoxy)propoxy-2-hydroxy-3-propylacetophenone and the resultant mixture was stirred overnight at room temperature. To the reaction mixture thus obtained was added dilute hydrochloric acid and the product was extracted with toluene. The extract thus obtained was washed with water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was subjected to silica gel column chromatography and eluted with a mixture of toluene and ethyl acetate (4 : 1) to provide 260 mg of 2-hydroxy-4-[2-hydroxy-3-[(5-mercapto-1,3,4-thiadiazol-2-yl)thio]-propoxy]-3-propylacetophenone as an oily product. Nuclear magnetic resonance spectra (CDCl₃, TMS internal standard, ppm) 0.92(t, 3H), 1.2-1.8(m, 2H), 2.56(s, 3H), 2,63(t, 2H), 3,48(dd, 2H), 4.0-4.2(m, 2H), 4.2-4.6(m, 1H), 6,42(dd, 1H), 7.61(d, 1H), 12.7(s, 1H). Example 2 A mixture of 2 g of 4-(3-bromopropoxy)-2-hydroxy-3-propylacetophenone, 1.6 g of 2-amino-5-mercapto-1,3,4-thiadiazole, 1.6 g of potassium carbonate, and 20 ml of N,N-dimethylformamide was stirred for one hour at 20 to 30°C and after addition of 100 ml of water to the reaction mixture thus obtained, the product was extracted with ethyl acetate. The extract was washed with water, dried over anhydrous magnesium sulfate, and then the solvent was distilled off. The residue thus formed was subjected to silica gel column chromatography and eluted with toluene to provide 2.3 g of 4-[3-[(5-amino-1,3,4-thiadiazol-2-yl)thio]propoxy]-2-hydroxy-3-propylacetophenone. Melting point: 144 to 145°C Elemental analysis for C₁₆H₂₁N₃O₃S₂: C H N S Calculated: 52.29% 5.76% 11.43% 17.45% Found: 52.09% 5.71% 11.58% 17.61% Examples 3 to 13 By following the same procedure as Example 2 the following compounds were obtained: Example 3 Starting compound: Desired compound: 2-Hydroxy-3-propyl-4-[3-[(2-thiazolin-2-yl)thio]propoxy]acetophenone Physicochemical properties: 1) Oily product ii) Nuclear magnetic resonance spectra (TMS, CDCl₃, ppm) 0.92(3H, t, J=6Hz), 1.2-1.8(2H), 2.0-2.8(4H), 2,55(3H, s), 3.2-3.5(4H), 4.0-4.3(4H), 6.38 (1H, d, J=9Hz), 7.56(1H, d, J=9Hz), 12.7(1H). Example 4 Starting compound: Desired compound: 2-Hydroxy-3-propyl-4-[3-[(1H-1,2,3-triazol-4-yl)thio]propoxy]acetophenone Physicochemical properties: i) Oily product ii) Nuclear magnetic resonance spectra (TMS, CDCl₃, ppm) 0.8-1.1(3H), 1.2-1.8(2H), 2.0-2.8(5H), 2.55 (3H, s), 3.0-3.2(1H), 3.9-4.3(2H), 4.5-4.7 (1H), 6.3-6.4(1H), 7.5-7.6(2H), 12.8(1H) Example 5 Starting compound: Desired compound: 4-[3-[(5-Amino-2H-1,2,4-triazol-3-yl)thio]propoxy]-2-hydroxy-3-propylacetophenone Physicochemical properties: i) Melting point: 171 to 172°C ii) Elemental analysis for C₁₆H₂₂N₄O₃S: C H N Calculated: 54.84% 6.33% 15.99% Found: 55.07% 6.62% 15.77% Example 6 Starting compound: Desired compound: 2-Hydroxy-4-[3-[(6-hydroxymethyl-4-oxo-4H-pyran-3-yl)oxy]propoxy]-3-propylacetophenone Physicochemical Properties: i) Melting point: 84 to 87°C ii) Elemental analysis for C₂₀H₂₄O₇: C H Calculated: 63.82% 6.43% Found: 63.73% 6.67% Example 7 Starting compound: Desired compound: 2-Hydroxy-4-[[3-(5-mercapo-1,3,4-thiadiazol-2-yl)thio]propoxy]-3-propylacetophenone Physicochemical Properties: i) Melting point: 127 to 129°C ii) Elemental analysis for C₁₆H₂₀N₂O₃S₃: C H N S Calculated: 49.97% 5.24% 7.28% 25.02% Found: 50.00% 5.33% 7.19% 24.82% Example 8 Starting compound: Desired compound: Methyl 6-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-2-methylthio-4-pyrimidinecarboxylate Physicochemical properties: i) Melting point: 99 to 100°C ii) Nuclear magnetic reasonace spectra (TMS, CDCl₃, ppm) 1.93 (3H, t, J=6Hz), 1.3-1.7(2H), 2.0-2.8(4H), 2.55(3H, s), 2.58 (3H, s), 3.3-3.5(2H), 3.92 (3H, s), 4.0-4.3(2H), 6.4-7.7(3H), 12.7(1H) Example 9 Starting compound: Desired compound: 4-[4-[(2-Amino-1,3,4-thiadiazol-5-yl)thio]butoxy]-2-hydroxy-3-propylacetophenone Physicochemcial properties: i) melting point: 107 to 108°C ii) Elemental analysis for C₁₇H₂₃N₃O₃S₂: C H N S Calculated: 53.52% 6.08% 11.01% 16.81% Found: 53.24% 5.89% 10.97% 16.74% Example 10 Starting compound: Desired compound: 4-[3-(2-Benzothiazolylthio)-propoxy]-2-hydroxy-3-propylacetophenone Physicochemical properties: i) Oily product ii) Elemetal analysis for C₂₁H₂₃NO₃S₂: C H N Calculated: 62.81% 5.77% 3.49% Found: 62.98% 5.98% 3.36% Example 11 Starting compound: Compound of Reference Example 2 Desired compound: Ethyl 4-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]butyrate Physicochemical properties: i) Oily product ii) Elemental analysis for C₂₂H₃₀N₂O₅S₃: C H N S Calculated: 52.99% 6.06% 5.62% 19.29% Found: 52.99% 6.11% 5.53% 19.18% Example 12 Starting compound: Desired compound: 4-[3-[(6-Aminobenzothiazol-2-yl)thio]propoxy]-2-hydroxy-3-propylacetophenone Physicochemical properties: i) Oily product ii) Nuclear magnetic reasonacen spectra (CDCl₃, TMS, ppm) 1.95(s,3H), 1.2-2.0(2H,), 2.53(s, 3H), 2.0-2.9(4H), 4.48(t,3H), 3.4-4.0(2H, -NH₂), 4.17(t,3H), 6.2-7.8(5H), 12.70(1H) Example 13 Starting compound: Desired compound: 4-[3-(2-Benzimidazolylthio)propoxy]-2-hydroxy-3-propylacetophenone Physicochemcial Properties: i) Melting point: 143 to 146°C ii) Elemental analysis for C₂₁H₂₄N₂O₃S: C H N Calculated: 65.60% 6.29% 7.29% Found: 65.46% 6.34% 7.25% Example 14 A mixture of 21.87 g of 4-(3-chloropropoxy)-2-hydroxy-3-propylacetophenone, 18.18 g of ethyl [(5-mercapto-1,3,4-thiadiazol-2-yl)thio]acetate, 12.7 g of anhydrous potassium carbonate, and 80 ml of methyl ethyl ketone was refluxed for 2.5 hours with vigorous stirring. After cooling, insoluble matters were filtered off and the filtrate was concentrated under reduced pressure. To the residue thus formed were added 200 ml of ethyl acetate and 150 ml of toluene and the mixture was washed with a dilute aqueous solution of sodium hydroxide and water, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure. The residue thus obtained was subjected to silica gel column chromatography and eluted with a mixture of toluene and ethyl acetate (10 : 1) to provide 33 g of ethyl [[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]acetate. Melting point: 71 to 72.5°C Elemental analysis for C₂₀H₂₆N₂O₅S₃: C H N S Calculated: 51.04 5.57% 5.95% 20.44% Found: 51.07% 5.49% 5.79% 20.17% Examples 15 to 18 By following the procedure of Example 14, the following compounds were prepared. Example 15 Starting compound: and the compound of Reference Example 5 Desired compound: Ethyl 5-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]valerate Physicochemical properties: i) Oily product ii) Nuclear magnetic resonance spectra (CDCl₃, TMS, ppm) 0.92(t, 3H), 1.24(t, 3H), 1.50-2.0(m, 6H), 2.34(2H), 2.54(s, 3H), 3,28(t, 2H), 3,46(t, 2H), 3.8-4.4(4H), 6.42(d, 1H), 7.58(d, 1H), 12.68(s, 1H) Example 16 Starting compound: Compound of Reference Example 6 and Desired compound: Ethyl 6-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]hexanoate Physicochemical properties: i) Oily product ii) Nuclear magnetic reasonance spectra (CDCl₃, ppm) 0.92(t,3H), 1.24(t,3H), 1.3-2.0(8H), 2.1-2.5 (4H), 2.54(s, 3H), 3.28(t,2H), 3.48(t,2H), 4.0-4.3(4H), 6.43(d,1H), 7.60(d, 1H), 12.7 (s.1H) Example 17 Starting compound: and Compound of Reference Example 8 Desired compound: Ethyl 2-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4,-thiadiazol-2-yl]thio]propionate Physicochemcical properties: i) Oily product ii) Elemental analysis for C₂₁H₂₈N₂O₅S₃: N S Calculated: 5.78% 19.85% Found: 5.85 20.05% Example 18 Starting compound: and Compound of Reference example 7 Desired compound: Ethyl 4-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]valerate Physicochemical properties: i) Oily product ii) Nuclear magnetic reasonacne spectra (CDCl₃, TMS, ppm) 0.97(t,3H), 1.26(t,3H), 1.50 (d, 3H), 1.40-1.80(2H), 2.36(t,2H), 2.60(s,3H), 3.52 (t, 2H), 3.90(q,1H), 4.0-4.4(4H), 6.46(d,1H), 7.63(d,1H0, 12.7(s, 1H) Example 19 Following the same procedure as Example 14 using 0.45 g of 2,4-dihdyroxy-3-propylacetophenone and 0.75 g of ethyl [[5-(3-bromopropyl)thio-1,3,4-thiadiazol-2-yl]thio]acetate gave 0.2 g of ethyl [[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]acetate. The properties of the product obtained were the same as those of the product obtained in Example 14. Example 20 A mixture of 596 mg of 4-(3-bromopropoxy)-2-hydroxy-3-propylacetophenone, 372.4 mg of ethyl [(5-mercapto-1,3,4-thiadiazol-2-yl)thio]acetate, 326 mg of anhydrous potassium carbonate, and 5 ml of N,N-dimethylformamide was stirred for 2 hours at room temperature. The reaction mixture thus obtained was concentrated under reduced pressure and after addition of chloroform, the mixture was washed with water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue thus formed was subjected to silica gel column chromatography and eluted with a mixture of toluene and ethyl acetate (10 : 1) to provide 663.3 mg of ethyl [[5-[[3-(4-acetyl-3-hydroxy-2-propoxyphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]acetate. The properties of the compound thus obtained were the same as those of the compound obtained in Example 14. Example 21 A mixture of 3.1 g of 4-(3-bromopropoxy)-2-hydroxy-3-propylacetophenone, 2.4 g of [(5-mercapto-1,3,4-thiadiazol-2-yl)thio]acetic acid, 3 g of potassium carbonate, and 30 ml of N,N-dimethylformamide was stirred for 3 hours at room temperature. After addition of 150 ml of water to the reaction mixture obtained, the product was extracted with ethyl acetate. The separated aqueous layer was acidified with 10% hydrochloric acid, and extracted with ethyl acetate. The extract was washed with water, dried over anhydrous magnesium sulfate, and then the solvent was distilled off under reduced pressure to provide a solid material. The solid material was recrystallied from ethanol to provide 2.5 g of [[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]acetic acid. Melting point: 129 to 130°C Elemental analysis for C₁₈H₂₂N₂O₅S₃: C H N S Calculated: 48.85% 5.01% 6.33% 21.74% Found: 48.78% 5.13% 6.29% 21.49% Example 22 By following the same procedure as Example 21 using 100 mg of 2-hydroxy-4-[[-(5-mercapto-1,3,4-thiadiazol-2-yl)thio]propoxy]-3-propylacetophenone obtained in Example 7 and 40 mg of bromoacetic acid as the starting materials, 70 mg of [[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]-thio]-1,3,4-thiadiazol-2-yl]thio] acetic acid was obainted. The compound thus obtained had the same properties as those of the compound obtained in Example 21. Example 23 A mixture of 1.3 g of 4-(4-bromobutoxy)-2-hydroxy-3-propylacetophenone, obtained in Reference Example 12, 1.0 g of [5-mercapto-1,3,4-thiadiazol-2-yl)thio]acetic acid, 1.0 g of anhydrous potassium carbonate, and 5 ml of N,N-dimethylformamide was stirred for 3 hours at 50°C. The reaction mixture thus obtained was mixed with 30 ml of water, washed with toluene, acidified with dilute hydrochloric acid, and extracted with ethyl acetate. The extract thus formed was washed with water, dried under anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue thus formed was recrystallized from ethyl acetate to provide 1.15 g of [[5-[[4-(4-acetyl-3-hydroxy-2-propylphenoxy)butyl]thio]-1,3,4-thiadiazol-2-yl]thio]acetic acid. Melting point: 123 to 124.5°C. Elemental analysis for C₁₉H₂₄N₂O₅S₃: C H N S Calculated: 49.98% 5.30% 6.14% 21.07% Found: 49.76% 5.29% 6.07% 21.13% Examples 24 to 27 By following the procedure of Example 23, the following compounds were prepared: Example 24 Starting compound: The compound of Reference Example 1 and the compound of Reference Example 13 Desired compound: [[5-[[5-(4-Acetyl-3-hydroxy-2-propylphenoxy)pentyl]thio]-1,3,4-thiadiazol-2-yl]thio]acetic acid Physicochemical properties: i) Melting point: 107 to 108°C ii) Elemental analysis for C₂₀H₂₆N₂O₅S₃ C H N S Calculated: 51.04% 5.57% 5.95% 20.44% Found: 50.81% 5.64% 5.98% 20.40% Example 25 Starting compound: The compound of Reference Example 1 and the compound of Reference Example 11 Desired compound: [[5-[[2-(4-Acetyl-3-hydroxy-2-propylphenoxy)ethyl]thio]-1,3,4-thiadiazol-2-yl]thio]acetic acid Physicochemical properties: i) Melting point: 135 to 137°C ii) Nuclear magnetic resonance spectra (DMSO-d₆, TMS, ppm) 0.98(t, 3H), 1.44(m, 2H), 2.60(s, 3H), 3,72(t, 2H), 4.16(d, 2H), 4.40(t, 2H), 6.66 (d, 1H), 2.78(d, 1H), 12.81(s, 1H) Example 26 Starting compound: and Compound of Reference example 9 Desired compound: 3-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]propionic acid Physicochemical properties: i) Melting point 102 to 104°C ii) Elemental analysis for C₁₉H₂₄N₂O₅S₃: N S Calculated: 6.14% 21.06% Found: 6.28% 21.03% Example 27 Starting compound: Desired compound: 5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-3-hydroxy-4-isothiazol carboxylic acid Physicochemical properties: i) Melting point 182 to 184°C ii) Elemental analysis for C₁₈H₂₁NO₆S₂: C H H S Calculated: 52.54% 5.14% 3.40% 15.58% Found: 52.23% 4.96% 3.20% 15.48% Example 28 To a solution of 0.28 g of 4-[3-[(5-amino-1,3,4-thiadiazol-2-yl)thio]propoxy]-2-hydroxy-3-propylacetophenone obtained in Example 2 dissolved in 5 ml of pyridine were added 0.28 g of mono-p-methoxybenzyl malonate, 0.20 g of dicyclohexylcarbodiimide, and 10 mg of p-toluenesulfonic acid, and the mixture obtained was stirred for 3 hours at room temperature. Insoluble matters were filtered off and the filtrate obtained was concentrated under reduced pressure. To the residue thus formed was added 30 ml of water and the product was extracted with 20 ml of toluene. The extract thus obtained was washed with water, dried over anhydrous magnesium sulfate, and then the solvent was distilled off to provide a solid material. The solid material was washed with methanol and dried to provide 0.25 g of p-methoxybenzyl 3-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]amino]-3-oxopropionate. Melting point: 133 to 135°C Elemental analysis for C₂₇H₃₁N₃O₇S₂: C H N S Calculated: 56.53% 5.45% 7.32% 11.18% Found: 56.81% 5.46% 7.19% 10.96% Examples 29 to 32 By following the same procedure as in Example 28, the following compounds were prepared: Example 29 Starting compound: Compound of Example 2 and Desired compound: Ethyl 4-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]amino]-4-oxobutyrate Physicochemical properties: i) Melting point: 129 to 131°C ii) Elemental analysis for C₂₂H₂₉N₃O₆S₂: C H N Calculated: 53.32% 5.90% 8.48% Found: 53.14 5.76 8.47 Example 30 Starting compound: Compound of Example 9 and Desired compound: p-Methyoxybenzyl 3-[[5-[[4-(4-acetyl-3-hydroxy-2-propylphenoxy)butyl]-thio]-1,3,4-thiadiazol-2-yl]amino]-3-oxopropionate Physicochemical properties: i) Melting point 141 to 143°C ii) Nuclear magnetic resonance spectra (CDCl₃, TMS, ppm) 1.90(t,3H), 1.0-2.0(8H), 2.60(s,3H), 3.1-3.4(2H), 3.68(s,2H), 3.80(s,3H), 3.9-4.2 (2H), 5.12(s,2H), 6.15-7.4(7H), 12.7(s,1H) Example 31 Starting compound: Compound of example 5 and Desired compound: p-Methoxybenzyl 3-[[2-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1H-1,2,4-triazol-3-yl]amino]-3-oxopropionate Physicochemical properties: i) Melting point: 151 to 153°C ii) Elemental analysis for C₂₇H₃₂N₄O₇S: C H N Calculated: 58.26% 5.79% 10.07% Found: 58.24% 5.83% 9.90% Example 32 Starting compound: Compound of Example 12 and Desired compound: p-Methoxybenzyl 3-[[2-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]benzothiazol-6-yl]amino]-3-oxopropionate Physicochemical properties: i) Melting point: 103 to 105°C ii) Elemental analysis for C₃₂H₃₄N₂O₇S₂: C H N Calculated: 61.72% 5.50% 4.50% Found: 61.77% 5.44% 4.39% Example 33 In a solution of 1.5 g of potassium hydroxide in 30 ml of 90% methanol was dissolved 0.9 g of p-methoxybenzyl ester obtained in Example 28 and the mixture was allowed to stand for 30 minutes at room temperature; 30 ml of water was added to the reaction mixture thus obtained. Then, methanol was distilled off from the reaction mixture and the aqueous solution thus obtained was washed with 30 ml of ethyl acetate, acidified with 10% hydrochloric acid, and then extracted with 30 ml of ethyl acetate. The extract thus obtained was washed with water, dried over anhydrous magnesium sulfate, and then the solvent was distilled off to provide a solid material. The solid material was washed with chloroform and dried to provide 0.5 g of 3-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]amino]-3-oxopropionic acid. Melting point: 172 to 174°C Elemental analysis for C₁₉H₂₃N₃O₆S₂: C H N S Calculated 50.32% 5.11% 9.26% 14.14% Found: 50.95% 5.01% 9.29% 13.93% Examples 34 to 39 By following the procedure of Example 33, the following compounds were prepared. Example 34 Starting compound: The compound of Example 29 Desired compound: 4-[[5-[[3-(4-Acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]amino]-4-oxobutyric acid Physicochemical properties: i) Melting point: 204 to 206°C ii) Elemental analysis for C₂₀H₂₅N₃O₆S₂: C H N Calculated: 51.38% 5.39% 8.99% Found: 51.18% 5.37% 8.99% Example 35 Starting compound: The compound of Example 30 Desired compound: 3-[[5-[[4-(4-Acetyl-3-hydroxy-2-propylphenoxy)butyl]thio]-1,3,4-thiadiazol-2-yl]amino]-3-oxopropionic acid. Physicochemical properties: i) Melting point: 168 to 170°C ii) Elemental analysis for C₂₀H₂₅N₃O₆S₂: C H Calculated: 51.38% 5.39% Found: 51.60% 5.68% Example 36 Starting compound: The compound of Example 46 Desired compound: N-[5-[[3-(4-Acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]oxamic acid Physicochemical properties: i) Melting point: 172 to 175°C (decompd.) ii) Elemental analysis for C₁₈H₂₁N₃O₆S₂: C H N Calculated: 49.19% 4.82% 9.56% Found: 49.28% 4.80% 9.43% Example 37 Starting compound: Compound of Exmple 8 Desired compound: 6-[[3-(4-Acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-2-methylthio-4-pyrimidinecarboxylic acid Physicochemical properties: i) Melting point: 125 to 128°C ii) Nuclear magnetic resonance spectra (TMS, CDCl₃ ppm) 0.92 (3H, t, J=6Hz), 1.2-1.8(2H), 2.1-2.8 (4H), 2.55(3H, s), 2.59(3H, s), 3.3 -3.6(2H) 4.1-4.3(2H), 6.42(1H, d, J=9Hz), 7.5-7.7(2H) Example 38 Starting compound: Compound of Example 11 Desired compound: 4-[[5-[[3-(4-Acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]butyric acid Physicochemical properties: i) Melting point: 100 to 101°C ii) Elemental analysis for C₂₀H₂₆N₂O₅S₃: C H N S Calculated: 51.04% 5.57% 5.95% 20.44% Found: 51.18% 5.66% 5.74% 20.44% Example 39 Starting compound: Compound of Example 32 Desired compound: 3-[[2-[[3-(4-Acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]benzothiazol-6-yl]amino]-3-oxopropionic acid Physicochemical Properties: i) Melting point: 148 to 150°C ii) Elemental analysis for C₂₄H₂₆N₂O₆S₂: C H N Calculated: 57.35% 5.21% 5.57% Found: 57.18% 5.19% 5.56% Example 40 To a mixture of 4.2 g of ethyl [[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]acetate obtained in Example 14 and 30 ml of methanol was added 20 ml of 5% aqueous sodium hdyroxide and the mixture was stirred for 30 minutes. Then, 30 ml of water was added to the reaction mixture and methanol was removed under reduced pressure. The residue thus formed was washed with ethyl acetate, acidified with dilute hydrochloric acid, and extracted with ethyl acetate. The extract was washed with water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue thus formed was recrystallized from 90% ethanol to provide 3.07 g of [[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]acetic acid. The properties of the compound thus obtained were the same as those of the compound obtained in Example 21. Examples 41 to 45 Example 41 By following the procedure of Example 40, the following compounds were prepared Example 41 Starting compound: The compound of Example 15 Desired compound: 5-[[5-[[3-(4-Acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]valeric acid Physicochemical properties: i) Melting point 86 to 87°C ii) Elemental analysis for C₂₁H₂₈N₂O₅S₃: C H N S Calculated: 52.04% 5.82% 5.78% 19.85% Found: 51.82% 6.02% 5.72% 19.96% Example 42 Starting compound: The compound of Example 16 Desired compound: 6-[[5-[[3-(4-Acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]hexanoic acid Physicochemical properties: i) Melting point: 77 to 78°C ii) Elemental analysis for C₂₂H₃₀N₂O₅S .½H₂O C H N Calculated: 52.15% 5.97% 5.53% Found: 52.14% 6.21% 5.33% Example 43 Starting compound: Compound of Example 17 Desired compound: Sodium 2-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]propionic acid Physicochemical properties: i) Oily product ii) Nuclear magnetic resonance spectra (DMSO-d₆, TMS, ppm) 0.88(t,3H), 1.52(d,3H), 2.20(2H), 2.60(s,3H), 3,44(t,2H), 4.22(t,2H), 6.66(d,1H), 7.84(d,1H), 12.8(s,1H), Example 44 Starting compound: Compound of Example 18 Desired compound: 4-[[5-[[3-(4-Acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]valeric acid Physicochemical Properties: i) Oily product ii) Nuclear magnetic resonance spectra (CDCl₃, TMS, ppm) 0.92(t, 3H), 1.49(d,3H), 2.12(t, 2H), 2.60 (s, 3H), 3.50(t,2H), 4.18(t, 2H), 6.45(d,1H), 7.61(d,1H), 12.7(s,1H) Example 45 Starting compound: Compound of Example 50 Desired compound: [[5-[2-(4-Acetyl-3-hydroxy-2-propylphenoxy)acetamide]-1,3,4-thiadiazol-2-yl]thio]acetic acid Physicochemical Properties: i) Melting point: 224 to 226°C ii) Elemental analysis for C₁₇H₁₉N₃O₆S₂: C H N S Calculated: 47.99% 4.50% 9.88% 15.07% Found: 47.97% 4.41% 9.76% 14.94% Example 46 To a solution of 0.4 g of 4-[3-[(5-amino-1,3,4-thiadiazol-2-yl)thio]propoxy]-2-hydroxy-3-propylacetophenone obtained in Example 2 dissolved in 10 ml of pyridine was added a mixture of 0.2 g of ethyloxalyl chloride and 1 ml of toluene under cooling below -10°C and then the resultant mixture was stirred for 30 minutes at room temperature. The reaction mixture thus obtained was mixed with 50 ml of water and extracted with 30 ml of ethyl acetate. The extract was successively washed with water, 5% hydrochloric acid, and then water, dried, and then the solvent was distilled off under reduced pressure. The residue thus formed was subjected to silica gel column chromatography and eluted with a mixture of toluene and ethyl acetate (3 : 2) to provide 0.3 g of ethyl N-[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]oxamate. Melting point: 146 to 147°C Elemental analysis for C₁₈H₂₁O₆N₃S₂: C H N S Calculated: 49.19% 4.82% 9.56% 14.59% Found: 49.28% 4.80% 9.43% 14.56% Example 47 By following the same procedure as Example 22 using 2-hydroxy-4-[2-hydroxy-3-[(5-mercapto-1,3,4-thiadiazol-2-yl)thio]propoxy]-3-propylacetophenone obtained in Example 1 and bromoacetic acid as the starting materials, [[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)-2-hydroxypropyl]thio]-1,3,4-thiadiazol-2-yl]thio]acetic acid was obtained. Melting point: 72 to 75°C. Nuclear magnetic resonance spectra (CDCl₃. TMS internal standard, ppm) 0.92(t, 3H), 1.3-1.8(m, 2H), 2.54(s, 3H), 2.60(t, 2H), 3,60(t, 2H), 4.04(s, 2H), 4.0-4.2(m, 2H), 4.2-4.6(m, 1H), 6.42(d, 1H), 7.60(d, 1H), 12.7(s, 1H). Example 48 To a solution of 0.42 g of 4-(4-acetyl-3-hydroxy-2-propylphenoxy)butyric acid obtained in Reference Example 3 dissolved in 10 ml of pyridine were added 0.31 g of methyl [[5-amino-1,3,4-thiadiazol-2-yl)thio]-acetate, 0.4 g of dicyclohexylcarbodiimide, and 3 mg of p-toluenesulfonic acid and the mixture was stirred for 3 hours at room temperature. Insoluble matters were removed by filtration and the filtrate was concentrated. The solid residue thus formed was, without being purified, in a solution of 1 g of potassium hydroxide dissolved in 20 ml of 90% methanol and after filtering off insoluble matters, the filtrate was allowed to stand for 30 minutes at room temperature. To the reaction mixture thus obtained was added 20 ml of water and then methanol was distilled off under reduced pressure. The aqueous solution thus obtained was washed with 20 ml of ethyl acetate. The aqueous solution was acidified with 10% hydrochloric acid and extracted with ethyl acetate. The extract thus obtained was washed with water, dried over anhydrous magnesium sulfate, and then the solvent was distilled off to provide 0.3 g of [[5-[[4-(4-acetyl-3-hydroxy-2-propylphenoxy)butyrylamido]-1,3,4-thiadiazol-2-yl]-thio]acetic acid. Nuclear magnetic resonance spectra (CDCl₃, DMSO-d₆, ppm) 0.87(3H, t), 1.1-1.7(2H), 2.57(3H, S), 1.9-3.0(6H), 4,07(2H, s), 4.11(2H, t), 6.61(1H, d), 7.78(1H, d), 12.80(1H, s) Example 49 In a mixture of 1.5 ml of trifluoroacetic acid and 0.1 ml of anisole was dissolved 100 mg of p-methoxybenzyl 3-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,2,4-triazol-3-yl]amino]-3-oxopropionate obtained in Example 31 at 10 to 20°C and after stirring the solution thus obtained for 30 minutes, trifluoroacetic acid was distilled off under reduced pressure. The residue thus formed was mixed with 20 ml of water and extracted with 20 ml of ethyl acetate. The extract was washed with water, dried over anhydrous magnesium sulfate, and then the solvent was distilled off to provide a solid product. The solid product was washed with methylene chloride and dried to provide 50 mg of 3-[[5-[[-3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,2,4-triazol-3-yl]amino]-3-oxopropionic acid. Melting point: 163 to 165°C Nuclear magnetic resonance spectra (CDCl₃- DMSO-d₆ (10 : 1), TMS, ppm) 0.90(3H, t), 1.2-1.8(2H), 2.0-2.8(4H), 2.55(3H, s), 3.25(3H, t), 3.48(2H, s), 4.17(2H, t), 6.44(1H, d), 7.61(1H, d), 12.63(1H, s). Example 50 To a mixture of 0.7 g of (4-acetyl-3-hydroxy-2-propylphenoxy)acetic acid obtained in Reference Example 10, 0.6 g of ethyl [[5-amino-1,3,4-thiadiazol-2-yl]thio]acetate, 10 ml of pyridine, and 1 mg of p-toluenesulfonic acid was added 0.57 g of dicyclohexylcarbodiimide and the mixture was stirred for one hour at room temperature. Insoluble matters were filtered off and the filtrate formed was concentrated under reduced pressure. To the residue thus formed was added ethyl acetate and the mixture was washed with dilute hydrochloric acid, washed with dilute aqueous sodium hydrogen carbonate, washed with water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue thus formed was recrystallized from 2-methoxyethanol to provide 0.8 g of [[5-[2-(4-acetyl-3-hydroxy-2-propylphenoxy)acetoamide]-1,3,4-thiadiazol-2-yl]thio]acetic acid. Melting point: 183 to 184°C Elemental analysis for C₁₉H₂₃N₃O₆S₂: C H N S Calculated: 50.32% 5.11% 9.26% 14.14% Found: 50.47% 5.14% 9.24% 14.38% Example 51 To a mixture of 0.5 g of [[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]acetic acid, 0.23 g of dicyclohexylcarbodiimide, 0.14 g of 1-hydroxybenzotriazole, and 50 ml of tetrahydrofuran was added a mixture of 0.27 g of N-methylhydroxylamine hydrochloride, 0.3 g of triethylamine, and 5 ml of N,N-dimethylformamide and the resultant mixture was stirred overnight at room temperature. Then, insoluble matters were filtered off and the filtrate thus formed was concentrated under reduced pressure. To the residue thus formed was added 100 ml of ethyl acetate and the mixture was washed with water, washed with a dilute aqueous solution of sodium hydrogencarbonate, and water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. To the residue thus obtained was added ethyl acetate, then insoluble materials were filtered off and the filtrate formed was concentrated. The residue thus obtained was recrystallized from a mixture of toluene and n-hexane to provide 0.18 g of 2-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]-N-hydroxy-N-methylacetamide. Melting point: 97 to 99°C Elemental analysis for C₁₉H₂₅N₃O₅S₃: N Calculated: 8.91% Found: 9.06% Example 52 (Tablet) Compound of Ex. 21 30 mg Lactose 104 mg Corn starch 57 mg Hydroxypropyl cellulose 4 mg Calcium carboxymethyl cellulose 4 mg Magnesium stearate 1 mg total 200 mg After uniformly mixing 30 g of compound of Ex. 21, 104 g of lactose and 57 g of corn starch, 40 ml of a 10%(w/w) aqueous solution of hydroxypropyl cellulose was added to the mixture and the resultant mixture was granulated by a wet granulation method. The granules thus obtained were mixed with 4 g of calcium carboxymethyl cellulose and 1 g of magnesium stearate and the mixture was press-tableted into tablets (200 mg per tablet). Example 53 (Capsule) Compound of Ex. 21 30 mg Crystalline cellulose 40 mg Crystalline lactose 129 mg Magnesium stearate 1 mg total 200 mg The above components each in an amount 1000 times the foregoing amount were mixed and then filled into gelatin capsules to provide capsules (200 mg per capsule). Example 54 (Inhalation) After dissolving 0.1 g of compound of Ex. 21 in about 90 ml of a mixture of ethanol, propylene glycol and purified water (30:10:60 in weight ratio), the volume of the solution was adjusted to 100ml using the aforesaid mixture and 10 ml aliquots of the solution were filled into respective containers followed by sealing to provide an inhalation.

Claims: A heterocyclic compound of formula (I), or a salt thereof : wherein R¹ represents a C₁ to C₆ acyl group; R² represents a C₁ to C₆ alkyl group; A represents a C₁ to C₆ alkylene group which may be hydroxy-substituted; Y represents an oxygen or sulfur atom or a carbonylimino or iminocarbonyl group; represents a 5- or 6-membered heterocyclic ring which contains 1 to 3 hetero atoms selected from oxygen, sulfur and nitrogen, is bonded directly to Y, and may be fused with a benzene ring; and R³, R⁴, and R⁵, each of which may be present or absent, are the same or different and selected from C₁ to C₆ alkyl groups, groups of formula -A¹-R⁶ [wherein A¹ represents a C₁ to C₆ alkylene group and R⁶ represents a hydroxy, mercapto, carboxy, or (C₁ to C₆ alkoxy) carbonyl group], hydroxy and mercapto groups, C₁ to C₆ alkoxy groups, C₁ to C₆ alkylthio groups, groups of formula -Y¹-A²-R⁷ [wherein Y¹ represents an oxygen or sulfur atom, A² represents a C₁ to C₆ alkylene group, and R⁷ represents a carboxy group, a (C₁ to C₆ alkoxy) carbonyl group, a hydroxyaminocarbonyl group, a mono- or di-(C₁ to C₆ alkyl) aminocarbonyl group, or an N-(C₁ to C₆ alkyl)hydroxyaminocarbonyl group], oxo, thioxo and amino groups, groups of formula -NH-R⁸ [wherein R⁸ represents a carboxy (C₁ to C₆ alkyl) group or a (C₁ to C₆ alkoxy)carbonyl (C₁ to C₆ alkyl) group], groups of formula -NH-CO-R⁹ [wherein R⁹ represents a carboxy (C₁ to C₆ alkyl) group, a (C₁ to C₆ alkoxy) carbonyl (C₁ to C₆ alkyl) group, a (C₁ to C₆ alkoxy)phenyl (C₁ to C₆ alkoxy)carbonyl (C₁ to C₆ alkyl) group, a carboxy group or a (C₁ to C₆ alkoxy)carbonyl group], a carboxy group, and groups of formula -CO-R¹⁰ [ wherein R¹⁰ represents a C₁ to C₆ alkoxy group]. A compound according to claim 1 wherein Y is a sulfur atom or a carbonylimino group and R³, R⁴, and R⁵, each of which may be present or absent, are the same or different and selected from groups of formula -A¹-OH, hydroxy, mercapto, and C₁ to C₆alkylthio groups, groups of formula -Y¹-A²-R⁷ [wherein Y¹ is a sulfur atom, A² is a C₁ to C₆ alkylene group, and R⁷ is a carboxy group, a (C₁ to C₆ alkoxy)carbonyl group, or an N-(C₁ to C₆ alkyl)-hydroxyaminocarbonyl group], oxo, thioxo, and amino groups, groups of formula -NH-R⁸, groups of formula -NH-CO-R⁹, a carboxy group, and groups of formula -CO-R¹⁰. A compound according to claim 1 or 2 wherein R¹ is an acetyl group, R² is a propyl group, A is an alkylene group having 1 to 5 carbon atoms, Y is a sulfur atom, is a 1,3,4-thiadiazole ring, and R³, R⁴, and R⁵, each of which may be present or absent, are the same or different and selected from hydroxy and mercapto groups, groups of formula -Y¹-A²-R⁷ [wherein Y¹ is a sulfur atom, A² is a C₁ to C₆ alkylene group, and R⁷ is a carboxy group, (C₁ to C₆ alkoxy)carbonyl group, or an N-(C₁ to C₆ alkyl)-hydroxyaminocarbonyl group], an amino group, and groups of formula NH-CO-R⁹. A compound according to claim 1 or 2 wherein R¹ is an acetyl group; R² is a propyl group, A is an alkylene group having 1 to 5 carbon atoms; Y is a sulfur atom; is a pyrimidine ring; and R³, R⁴, and R⁵ , each of which may be present or absent, are the same or different and selected from hydroxy, mercapto, C₁ to C₆ alkythio, amino, and carboxy groups, and groups of formula -COR¹⁰. A compound according to claim 1 which is [[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)-propyl]thio]-1,3,4-thiadiazol-2-yl]thio]acetic acid or a salt thereof; 3-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]amino]-3-oxopropionic acid or a salt thereof; 4-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]butyric acid or a salt thereof; 5-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]valeric acid or a salt thereof; 2-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4-thiadiazol-2-yl]thio]-N-hydroxy-N-methylacetamide or a salt thereof; or 6-[[-3-(4-acetyl-3-hydroxy-2-propylphenoxy)-propyl]thio]-2-methylthio-4-pyrimidinecarboxylic acid or a salt thereof. A process of producing a compound of formula (I) wherein R¹ represents a C₁ to C₆ acyl group; R² represents a C₁ to C₆ alkyl group; A represents a C₁ to C₆ alkylene group which may be hydroxy-substituted; Y represents an oxygen or sulfur atom or a carbonylimino or iminocarbonyl group; represents a 5- or 6-membered heterocyclic ring which contains 1 to 3 hetero atoms selected from oxygen, sulfur and nitrogen, is bonded directly to Y, and may be fused with a benzene ring; and R³, R⁴, and R⁵, each of which may be present or absent, are the same or different and selected from C₁ to C₆ alkyl groups, groups of formula -A¹-R⁶ [wherein A¹ represents a C₁ to C₆ alkylene group and R⁶ represents a hydroxy, mercapto, carboxy, or (C₁ to C₆ alkoxy) carbonyl group], hydroxy and mercapto groups, C₁ to C₆ alkoxy groups, C₁ to C₆ alkylthio groups, groups of formula -Y¹-A²-R⁷ [wherein Y¹ represents an oxygen or sulfur atom, A² represents a C₁ to C₆ alkylene group, and R⁷ represents a carboxy group, a (C₁ to C₆ alkoxy) carbonyl group, a hydroxyaminocarbonyl group, a mono- or di-(C₁ to C₆ alkyl) aminocarbonyl group, or an N-(C₁ to C₆ alkyl)-hydroxyaminocarbonyl group], oxo, thioxo and amino groups, groups of formula -NH-R⁸ [wherein R⁸ represents a carboxy (C₁ to C₆ alkyl) group or a (C₁ to C₆ alkoxy)carbonyl (C₁ to C₆ alkyl) group], groups of formula -NH-CO-R⁹ [wherein R⁹ represents a carboxy (C₁ to C₆ alkyl) group, a (C₁ to C₆ alkoxy) carbonyl (C₁ to C₆ alkyl) group, a (C₁ to C₆ alkoxy)phenyl (C₁ to C₆ alkoxy)carbonyl (C₁ to C₆ alkyl) group, a carboxy group or a (C₁ to C₆ alkoxy)carbonyl group], a carboxy group, and groups of formula -CO-R¹⁰ [ wherein R¹⁰ represents a C₁ to C₆ alkoxy group] which comprises either : (a) reacting halogen compound of formula (II) (wherein R¹, R² and A are as defined above and X represents halogen) and hydroxy- or mercapto-compound of formula (III) or alkali metal-substituted compound thereof (wherein R³, R⁴ and R⁵ are as defined above, M represents hydrogen or alkali metal, and Y² represents an oxygen or sulfur atom); or (b) reacting hydroxy- or mercapto-compound of formula (VIII) or alkali metal-substituted compound thereof (wherein R¹, R², A, Y, R⁴, R⁵, Y¹ and M are as defined above) and halogen compound of formula (IX) X-A²-R⁷ (IX) (wherein X, A² and R⁷ are as defined above); or (c) hydrolizing ester compound of formula (Ii) [wherein R¹, R², A, Y, R⁴ and R⁵ are as defined above and Y³ represents a single bond, an oxygen or sulfur atom or an imino group (-NH-); A³ represents a single bond or a C₁ to C₆ alkylene group or when Y³ is imino, may instead be a carbonyl or carbonyl (C₁ to C₆ alkylene) group; and R¹³ represents C₁ to C₆ alkyl group or a (C₁ to C₆ alkoxy) phenyl (C₁ to C₆ alkyl) group]; or (d) reacting dihydroxybenzene derivative of formula (XII) or alkali metal-substituted compound thereof (wherein R¹, R² and M are as defined above) and halogen compound of formula (XIII) wherein X, A, Y and are as defined above and R 3' , R 4' and R 5' , which may be present or absent, are the same or different and selected from C₁ to C₆ alkyl groups, groups of formula -A¹-R 6' [wherein A¹ is as defined above and R 6' represents a (C₁ to C₆ alkoxy)carbonyl group], a hydroxyl group, C₁ to C₆ alkoxy groups, C₁ to C₆ alkylthio groups, groups of formula -Y¹-A²-R 7' [wherein Y¹ and A² are as defined above and R⁷ represents a (C₁ to C₆ alkoxy)carbonyl group, a hydroxyaminocarbonyl group, a mono- or di-(C₁ to C₆ alkyl) amino-carbonyl group or N-(C₁ to C₆ alkyl)-hydroxyaminocarbonyl group), an oxo group (=O=), an amino group, groups of formula -NH-R 8' [wherein R 8' represents a (C₁ to C₆ alkoxy)carbonyl (C₁ to C₆ alkyl) group], groups of formula -NH-CO-R 9' [wherein R 9' represents a (C₁ to C₆ alkoxy)carbonyl (C₁ to C₆ alkyl) group, a (C₁ to C₆ alkoxy)phenyl (C₁ to C₆ alkoxy)carbonyl (C₁ to C₆ alkyl) group or a (C₁ to C₆ alkoxy)carbonyl group), and groups of formula -CO-R¹⁰ [wherein R¹⁰ is as defined above]; or [e] esterifying compound of formula (Ij) below with alcohol R¹³OH or reactive derivative thereof (wherein R¹³ is as defined above). A process of producing a compound of formula I : wherein R¹ represents a C₁ to C₆ acyl group; R² represents a C₁ to C₆ alkyl group; A represents a C₁ to C₆ alkylene group may be hydroxy-substituted: Y represents an oxygen or sulfur atom or a carbonylimino or iminocarbonyl group; represents a 5- or 6-membered heterocyclic ring which contains 1 to 3 hetero atoms selected from oxygen, sulfur and nitrogen, is bonded directly to Y, and may be fused with a benzene ring; and R³, R⁴, and R⁵, each of which may be present or absent, are the same or different and selected from C₁ to C₆ alkyl groups, groups of formula -A¹-R⁶ [wherein A¹ represents a C₁ to C₆ alkylene group and R⁶ represents a hydroxy, mercapto, carboxy, or (C₁ to C₆ alkoxy) carbonyl group], hydroxy and mercapto groups, C₁ to C₆ alkoxy groups, C₁ to C₆ alkylthio groups, groups of formula -Y¹-A²-R⁷ [wherein Y¹ represents an oxygen or sulfur atom, A² represents a C₁ to C₆ alkylene group, and R⁷ represents a carboxy group, a (C₁ to C₆ alkoxy) carbonyl group, a hydroxyaminocarbonyl group, a mono- or di-(C₁ to C₆ alkyl) aminocarbonyl group, or an N-(C₁ to C₆ alkyl)-hydroxyaminocarbonyl group], oxo, thioxo and amino groups, groups of formula -NH-R⁸ [wherein R⁸ represents a carboxy (C₁ to C₆ alkyl) group or a (C₁ to C₆ alkoxy)carbonyl (C₁ to C₆ alkyl) group], groups of formula -NH-CO-R⁹ [wherein R⁹ represents a carboxy (C₁ to C₆ alkyl) group, a (C₁ to C₆ alkoxy) carbonyl (C₁ to C₆ alkyl) group, a (C₁ to C₆ alkoxy)phenyl (C₁ to C₆ alkoxy)carbonyl (C₁ to C₆ alkyl) group, a carboxy group or a (C₁ to C₆ alkoxy)carbonyl group], a carboxy group, and groups of formula -CO-R¹⁰ [ wherein R¹⁰ represents a C₁ to C₆ alkoxy group] which comprises either : (i) reacting carboxylic acid (IV) or reactive derivative thereof (wherein R¹, R² and A are as defined above) with amino compound (V) (wherein R³, R⁴ and R⁵ are as defined above); or (ii) reacting amine (VI) (wherein R¹, R² and A are as defined above) with carboxylic acid (VII) or reactive derivative thereof (wherein R³, R⁴ and R⁵ are as defined above); or (iii) reacting amino compound (Ie) (wherein R¹, R², A, Y, R⁴ and R⁵ are as defined above) with carboxylic acid (X) HOOC-R⁹ (X) or reactive derivative thereof (wherein R⁹ is as defined above); or (iv) reacting carboxylic acid (Ig) or reactive derivative thereof (wherein R¹, R², A, Y, R⁴, R⁵, Y¹ and A² are as defined above) with amine (XI) (wherein R¹¹ represents a hydrogen atom or a C₁ to C₆ alkyl group and R¹² represents a C₁ to C₆ alkyl group or a hydroxyl group); or (v) reacting epoxy compound (XIV) (wherein R¹ and R² are as defined above and A⁴ represents a single bond or a C₁ to C₆ alkylene group) with hydroxy- or mercapto-compound (XV) or alkali metal substituted compound thereof [wherein M, Y² and are as defined above and R 3'' , R 4'' and R 5'' , each of which may be present or absent, are the same or different and selected from C₁ to C₆ alkyl groups, a hydroxyl group, groups of formula -A¹-R 6'' (wherein A¹ is as defined above and R 6'' represents a hydroxyl,carboxy or (C₁ to C₆ alkoxy)carbonyl group), C₁ to C₆ alkoxy groups, C₁ to C₆ alkylthio groups, groups of formula -Y¹-A²-R⁷ (wherein Y¹, A² and R⁷ are as defined above) an oxo group, an amino group, groups of formula -NH-R⁸ (wherein R⁸ is as defined above), groups of formula -NH-CO-R⁹ (wherein R⁹ is as defined above), a carboxy group, and groups of formula -CO-R¹⁰ [wherein R¹⁰ is as defined above]. A process according to claim 6 or 7 including the step of converting the product to or from salt form. A pharmaceutical composition containing a compound according to any of claims 1 to 5. A composition according to claim 9 capable of antagonizing the actions of SRS-A or inhibiting the production and release of SRS-A and containing [[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio-1,3,4-thiadiazol-2-yl]thio]-acetic acid or a pharmaceutically acceptable salt thereof. A process according to claim 6 or 7 or 8 wherein compound (II) is 4-(3-halogenopropoxy)-2-hydroxy-3-propylacetophenone and compound(III)is[(5-mercapto-1,3,4,-thiadiazol-2-yl)thio]acetic acid; or compound (VIII) is 2-hydroxy-4-[[3-(5-mercapto-1,3,4-thiadiazol-2-yl)thio]propoxy]-3-propylacetophenone and compound (IX) is halogenaocetate; or ester (Ii) is (C₁ to C₆ alkyl)- or (C₁ to C₆ alkoxy)phenyl (C₁ to C₆ alkyl)-[[5-[[3-(4-acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]-1,3,4,-thiadiazol-2-yl]-thio]acetate.

Inventors: HIROMU HARA, KENICHI TOMIOKA, KIYOSHI MURASE, TOSHIYASU MASE, HIROMU, HARA, KENICHI, TOMIOKA, KIYOSHI, MURASE, TOSHIYASU, MASE
Applicants: YAMANOUCHI PHARMA CO LTD, YAMANOUCHI PHARMACEUTICAL CO. LTD.
Application year: 1985
Main classification: C07D285
IPC codes: C07D309, C07D285, C07D249, C07D275, C07D239, A61K31, C07D277