Compounds and compositions

Fungicidal compositions comprising as an active ingredient a compound of the general formula I ##STR1## wherein either R.sup.1 or R.sup.2 is the group ##STR2## in which X is an oxygen atom or a sulphur atom and R.sup.5 is straight chain alkyl group of 1 to 8 carbon atoms, branched chain alkyl group of 1 to 8 carbon atoms, cyclic alkyl group of 3 to 8 carbon atoms, alkenyl group, alkynyl group, hydroxyalkyl group phenyl group or a mono-, di- or tri- substituted phenyl group with substituents, which may be the same or different, chosen from the group consisting hydrogen alkyl, alkenyl, alkynyl, hydroxyalkyl, alkoxy, phenyl, halogen, trifluoromethyl, thiocyanate, nitro, cyano, amino, carboxy, alkoxycarbonyl, carbamoyl, N-alkylcarbamoyl and N,N-dialkylcarbamoyl; when R.sup.1 is the group ##STR3## then R.sup.3 is hydrogen, alkyl, alkenyl alkynyl, hydroxyalkyl, phenyl, CH.sub.2 CF.sub.3 or the group --CH.sub.2 COOR.sup.6 wherein R.sup.6 is alkyl, phenyl or substituted phenyl, and R.sup.2 and R.sup.4, which may be the same or different, are hydrogen, alkyl, alkenyl, alkynyl, hydroxalkyl, alkoxy, phenyl, halogen, trifluoromethyl, thiocyanate, nitro, cyano, amino, carboxy, alkoxycarbonyl, carbamoyl, N,alkylcarbamoyl, N,N-dialkylcarbamoyl, hydroxy or mercapto provided that R.sup.2 and R.sup.4 are not both hydrogen, hydroxy or mercapto; when R.sup.2 is the group ##STR4## then R.sup.3 is hydrogen, alkyl, alkenyl, alkynyl, hydroxyalkyl, phenyl or substituted phenyl, and R.sup.1 and R.sup.4, which may be the same or different, are hydrogen, alkyl, alkenyl, hydroxyalkyl, alkoxy, phenyl, substituted phenyl, halogen, trifluoromethyl, thiocyanate, nitro, cyano, amino, carboxy, alkoxycarbonyl, carbamoyl, N-alkylcarbamoyl, N,N-dialkylcarbamoyl, hydroxy or mercapto, provided that R.sup.1 and R.sup.3 are not both hydrogen and provided that R.sup.1 and R.sup.4 are not both hydroxy or mercapto; and an inert carrier material therefor.

This invention relates to new fungicidal compositions containing pyrazole 
derivatives as an active ingredient and to methods of combatting plant 
fungal diseases using them. 
Accordingly the present invention provides fungicidal compositions 
comprising as an active ingredient a compound of the general formula I 
##STR5## 
wherein either R.sup.1 or R.sup.2 is the group 
##STR6## 
in which X is an oxygen atom or a sulphur atom and R.sup.5 is straight 
chain alkyl group of 1 to 8 carbon atoms, branched chain alkyl group of 1 
to 8 carbon atoms, cyclic alkyl group of 3 to 8 carbon atoms, alkenyl 
group, alkynyl group, hydroxyalkyl group, phenyl group or a mono-, di- or 
tri- substituted phenyl group with subsituents, which may be the same or 
different, chosen from the group comprising hydrogen, alkyl, alkenyl, 
alkynyl, hydroxyalkyl, alkoxy, phenyl, halogen, trifluoromethyl, 
thiocyanate, thicyanate, nitro, cyano, amino, carboxy, alkoxycarbonyl, 
carbamoyl, N-alkylcarbamoyl and N,N-dialkylacarbamoyl; when R' is the 
group 
##STR7## 
then R.sup.3 is hydrogen, alkyl, alkenyl, alkynyl, hydroxyalkyl, phenyl, 
CH.sub.2 CF.sub.3 or the group --CH.sub.2 COOR.sup.6 wherein R.sup.6 is 
alkyl, phenyl or substituted phenyl, and R.sup.2 and R.sup.4, which may be 
the same or different, are hydrogen, alkyl, alkenyl, alkynyl, hydroxalkyl, 
alkoxy, phenyl, substituted phenyl, halogen, trifluoromethyl, thiocyanate, 
nitro, cyano, amino, carboxy, alkoxycarbonyl, carbamoyl, N-alkylcarbamoyl, 
N,N-dialkylcarbamoyl, hydroxy or mercapto provided that R.sup.2 and 
R.sup.4 are not both hydrogen, hydroxy or mercapto; when R.sup.2 is the 
group 
##STR8## 
then R.sup.3 is hydrogen, alkyl, alkenyl, alkynyl, hydroxyalkyl, phenyl or 
substituted phenyl, R.sup.1 and R.sup.4, which may be the same or 
different, are hydrogen, alkyl, alkenyl, hyroxyalkyl, alkoxy, phenyl, 
substituted phenyl, halogen, trifluoromethyl, thiocyanate, nitro, cyano, 
amino, carboxy, alkoxycarbonyl, carbamoyl, N-alkylcarbamoyl, 
N,N-dialkylcarbamoyl, hydroxy or mercapto, provided that R.sup.1 and 
R.sup.3 are not both hydrogen and provided that R.sup.1 and R.sup.4 are 
not both hydroxy or mercapto; and an inert carrier material therefor. 
Unless otherwise stated, by alkyl, alkenyl, alkynyl and hydroxyalkyl we 
mean a group containing from 1 to 4 carbon atoms. 
It is to be understood that when either R.sup.2 or R.sup.4 is a hydroxy or 
mercapto group the compounds of the invention may exist in a tautomeric 
form of the general formula II or III respectively, 
##STR9## 
wherein Y is an oxygen atom or a sulphur atom and R.sup.1, R.sup.2, 
R.sup.3 and R.sup.4 are as defined hereinabove. 
Preferred fungicidal compositions of the present invention comprise as an 
active ingredient a compound of the general formula I wherein R.sup.3 is 
hydrogen, alkyl, phenyl, or substituted phenyl; R.sup.4 is alkyl; and 
R.sup.2 is hydrogen, alkyl or halogen when R.sup.1 is the group 
--CONHR.sup.5 and R.sup.1 is hydrogen or alkyl when R.sup.2 is the group 
--CONHR.sup.5, wherein R.sup.5 is phenyl or a mono-, di- or trisubstituted 
phenyl group. Specific compounds useful as active ingredients in the 
pesticidal compositions of this invention are listed in Tables I, II, III 
and IV below. 
TABLE I 
______________________________________ 
Compounds of General Formula IV: 
##STR10## IV 
Com- Physical 
pound Characteristic 
No R.sup.3 R.sup.7 R.sup.8 
M.p.(.degree. C) 
______________________________________ 
1 CH.sub.2 CH.sub.2 OH 
H H 162-4 
2 CH.sub.2 COOCH.sub.2 CH.sub.3 
H H 172-4 
3 H H H 244-5 
4 H 2-CH.sub.3 H 230-2 
5 H 3-CH.sub.3 H 209-11 
6 H 3-Cl H 234-5 
7 H 4-Cl H 271-2 
8 H 3-Cl 4-Cl 259-60 
9 H 4-OCH.sub.2 CH.sub.3 
H 234-5 
10 H 2-NO.sub.2 H 224-5 
11 CH.sub.3 H H 161-3 
12 CH.sub.3 2-CH.sub.3 H 152-3 
13 CH.sub.3 3-CH.sub.3 H 159-61 
14 CH.sub.3 3-Cl H 155-6 
15 CH.sub.3 4-Cl H 206-7 
16 CH.sub.3 3-Cl 4-Cl 168-70 
17 CH.sub.3 4-OCH.sub.2 CH.sub. 3 
H 163-4 
18 CH.sub.3 2-NO.sub.2 H 168-70 
19 CH.sub.3 3-CF.sub.3 H 112-4 
20 Phenyl H H 182-3 
21 Phenyl 2-CH.sub.3 H 144-6 
22 Phenyl 3-CH.sub.3 H 148-9 
23 Phenyl 3-Cl H 143-5 
24 Phenyl 4-Cl H 218-9 
25 Phenyl 3-Cl 4-Cl 212-3 
26 Phenyl 4-OCH.sub.2 CH.sub.3 
H 193-4 
27 Phenyl 2-NO.sub.2 H 141-2 
______________________________________ 
table ii 
______________________________________ 
com- Physical 
pound Characteristic 
No Structural Formula M.p.(.degree. C) 
______________________________________ 
28 
##STR11## 185-6 
______________________________________ 
table iii 
______________________________________ 
compounds of General Formula V: 
##STR12## V 
Physical 
Compound Characteristic 
No R.sup.3 R.sup.7 M.p. (.degree. C) 
______________________________________ 
29 CH.sub.3 H 96-7 
30 CH.sub.3 2-CH.sub.3 158-60 
31 CH.sub.3 3-CH.sub.3 83-5 
32 CH.sub.3 3-Cl 115-7 
______________________________________ 
TABLE IV 
______________________________________ 
Compounds of General Formula VI: 
##STR13## VI 
Physical 
Compound Characteristic 
No R.sup.2 R.sup.7 R.sup.8 
M.p.(.degree. C) 
______________________________________ 
33 Cl H H 157-159 
34 Cl 3-Cl H 161-162 
35 H H H 91-92 
______________________________________ 
all of the compounds in Tables I, II, III and IV are new compounds with the 
exception of Compound 11 of Table I. Accordingly in a further aspect of 
our invention we provide new compounds of the general formula I 
##STR14## 
wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 have any of the meanings as 
defined hereinbefore except that R.sup.2, R.sup.3 and R.sup.4 may not be 
methyl when R.sup.1 is the group --CONHPh. 
The actual compounds set out in Tables I, II, III and IV of this 
specification are well-defined crystalline solids having accurately 
determinable melting points. 
The active compounds of our invention defined by the general formula I 
wherein R.sup.1 is the group 
##STR15## 
may be prepared by one of the three following methods: 
(a) bringing into reaction the appropriate 1,3-diketone (VII) and an 
isocyanate or isothiocyanate (VIII) and treating the resulting 
2-carbamoyl-1,3-diketone (or 2-thiocarbamoyl-1, 3-diketone) (IX) with 
hydrazine or an appropriate monosubstituted hydrazine (X); 
##STR16## 
(b) bringing into reaction with appropriate 2-alkoxycarbonyl-1,3-diketone 
(XI) hydrazine or monosubstituted hydrazine (X), hydrolysing the resulting 
ester (XII) to the corresponding acid (XIII) and derivatizing the acid 
(XIII) by methods well known to those skilled in the art; 
##STR17## 
(c) bringing into reaction the appropriate .alpha.-keto carboxylic acid 
ester (XIV) and a monosubstituted hydrazine (X), treating the resulting 
pyrazolone (XV) with the appropriate isocyanate or isothiocyanate (VIII) 
and aromatising the resulting carboxamidopyrazolone (XVI) using, for 
example, phosphorous oxychloride. 
##STR18## 
The active compounds of our invention defined by the general formula I 
wherein R.sup.2 is the group 
##STR19## 
may be prepared by treating the appropriate 1,3-diketocarboxylic acid 
ester (XVII) with hydrazine or the appropriately monosubstituted hydrazine 
(X), hydrolysing the resulting ester (XVIII) to the corresponding acid 
(XIX), and derivatizing the acid (XIX) by methods well known to those 
skilled in the art. 
##STR20## 
Accordingly, the invention also provides processes for the preparation of 
compounds of general formula I as hereinbefore defined. 
The compositions and compounds of this invention are useful in combatting 
various of the following list of fungal diseases: 
Septoria nodorum; (glume blotch) 
Uromyces viciae-fabae; (bean rust) 
Cladosporium cucumerinum; (gamosis) 
Puccinia recondita; (rust on wheat) 
Rhizoctonia solani; (root rot) 
Phytophthora infestans; (late blight on potato and tomato) 
Xanthomonas oryzae; (bacterial blight of rice) 
Piriculania oryzae; (blast on rice) 
Ustilago nuda; (loose smut) 
Tilletia foetida; (wheat bunt) 
Monolinia fructicola; (brown rot) 
Phytophthora cinnamomi; (cinnamon root rot) 
Gauemannomyces graminis; (take all) 
Compound Nos 13, 14 of Table I and 33 of Table IV are particularly active 
against Tilletia spp., Compound Nos 11, 12, 13 of Table I and 33 of Table 
IV are particularly useful against Rhizoctonia solani, Compound Nos 11, 14 
and 17 of Table I are particularly active against Uromyces viciae-fabae 
and Compound Nos 13 of Table I is also useful against Ustilago nuda and 
Puccinia recondita. 
A particularly useful feature of the activity of compounds of the present 
invention is their ability to move in a plant to combat an infection or 
infestation thereon remote from a site of initial application of a 
compound. Thus a compound of the invention, or a composition containing 
the same, may be applied to the soil surrounding the roots of a plant and 
taken up by the plant through its roots to combat pests on the plant. 
In this respect Compound Nos 12 and 13 are especially useful as agents to 
combat the disease Rhizoctonia solani. 
In use, the compositions or compounds of the invention may be applied in a 
number of ways. Thus their application can suitably be directly onto the 
foilage of the plants or to infected and/or infested areas thereof; 
alternately the soil surrounding the plant, or the stem of the plant, or 
soil in which seeds or plants are to be sown or planted is treated with 
the compositions or compounds of the invention. If desired, the seeds 
themselves can be similarly treated. 
According to a further feature of the invention, therefore, we provide a 
process of combatting undesired fungal infestations in plants which 
process comprises applying to said plants or to the locus of said plants a 
fungicidally effective amount of a composition or compound of the 
invention. 
The invention further includes a method of combatting fungal or insect 
infestations in plants which comprises applying to plant seeds a 
composition or compound of the invention. 
In yet a further aspect of the invention, therefore, we provide a process 
of treating seeds which process comprises treating said seeds prior to 
sowing with a fungicidally effective amount of a composition or compound 
of the invention. 
The compositions and compounds of the invention are useful for agricultural 
or horticultural purposes and the compound or type of composition used in 
any instance will depend upon the particular purpose for which it is to be 
used. 
Compositions comprising the invention compounds may be in the form of 
dusting powders or granules wherein the active ingredient is mixed with a 
solid diluent or carrier. Suitable solid diluents or carriers may be, for 
example, keolinite (china clay) montmorillonite, attapulgite, talc, 
pumice, silica, calcium carbonate, gypsum, powdered magnesia, Fuller's 
earth, Hewitt's earth and diatomaceous earth. Compositions for dressing 
seed, for example, may comprise an agent assisting the adhesion of the 
composition to the seed, for example, a mineral oil. 
The compositions may also be in the form of dispersible powders or grains 
comprising, in addition to the active ingredient, a wetting agent to 
facilitate the dispersion of the powder or grains in liquids. Such powders 
or grains may include fillers, suspending agents and the like. 
The compositions may also be in the form of liquid preparations to be used 
as dips or sprays which are generally aqueous dispersions or emulsions 
containing the active ingredient in the presence of one or more wetting 
agents, dispersing agents, emulsifying agents or suspending agents. 
Wetting agents, dispersing agents and emulsifying agents may be of the 
cationic, anionic, or non-ionic type. Suitable agents of the cationic type 
include, for example, quaternary ammonium compounds, for example, 
cetyltrimethylammonium bromide. Suitable agents of the anionic type 
include, for example, soaps, salts or aliphatic monoesters of sulphuric 
acid, for example sodium lauryl sulphate, salts of sulphonated aromatic 
compounds, for example sodium dodecylbenzene sulphonate, sodium, calcium, 
or ammonium lignosulphonate, butylnaphthalene sulphonate, and a mixture of 
the sodium salts of diisopropyl- and triisopropylnaphthalene sulphonic 
acids. 
Suitable agents of the non-ionic type include, for example, the 
condensation products of ethylene oxide with fatty alcohols such as oleyl 
alcohol or cetyl alcohol, or with alkyl phenols such as octylphenol, 
nonylphenol and octylcresol. Other nonionic agents are the partial esters 
derived from long chain fatty acids and hexitol anhydrides, the 
condensation products of the said partial esters with ethylene oxide, the 
lecithins, and block copolymers of ethylene oxide and propylene oxide. 
Suitable suspending agents are, for example, bentonite, pyrogenic silica, 
and hydrophilic colloids, for example polyvinylpyrrolidone and sodium 
carboxymethyl-cellulose, and the vegetable gums, for example gum acacia 
and gum tragancanth. 
The aqueous solutions, dispersions or emulsions may be prepared by 
dissolving the active ingredient or ingredients in an organic solvent 
which may contain one or more wetting, dispersing or emulsifying agents 
and then adding the mixture so obtained to water which may likewise 
contain one or more wetting, dispersing or emulsifying agents. Suitable 
organic solvents are ethylene dichloride, isopropyl alcohol, propylene 
glycol, diacetone alcohol, toluene, kerosene, methyl-naphthalene, xylenes 
and trichloroethylene. 
The compounds of the invention may also be formulated into compositions 
comprising capsules or microcapsules containing either the active 
ingredient itself, or a composition containing the active ingredient, and 
prepared by any of the known encapsulation or microencapsulation 
techniques. 
The compositions to be used as sprays may also be in the form of aerosols 
wherein the formulation is held in a container under pressure in the 
presence of a propellant such as fluorotrichlormethane or 
dichlordifluoromethane. 
By the inclusion of suitable additives, for example, for improving the 
distribution, adhesive power and resistance to rain on treated surfaces, 
the different compositions can be better adapted for the various uses for 
which they are intended. 
The compounds of this invention may also be conveniently formulated by 
admixing them with fertilizers. A preferred composition of this type 
comprises granules of fertilizer material incorporating, for example 
coated with, a compound of the invention. The fertilizer material may, for 
example, comprise nitrogen or phosphate-containing substances. 
In yet a further aspect of the invention, therefore, we provide a 
fertilizer comprising a compound of the invention as hereinbefore defined. 
The compositions which are to be used in the form of aqueous dispersions or 
emulsions are generally supplied in the form of a concentrate containing a 
high proportion of the active ingredient or ingredients, the said 
concentrate to be diluted with water before use. 
These concentrates are often required to withstand storage for prolonged 
periods and after such storage, to be capable of dilution with water in 
order to form aqueous preparations which remain homogeneous for a 
sufficient time to enable them to be applied by conventional spray 
equipment. The concentrates may conveniently contain from 10-85% by weight 
of the active ingredient or ingredients and generally from 25-60% by 
weight of the active ingredient or ingredients. When diluted to form 
aqueous preparations, such preparations may contain varying amounts of the 
active ingredient or ingredients depending upon the purpose for which they 
are to be used, but an aqueous preparation containing between 0.0001% and 
1.0% by weight of active ingredient or ingredients may be used. 
It is to be understood that the pesticidal compositions of this invention 
may comprise, in addition to a compound of the invention, one or more 
other compounds having biological activity.

Our invention is illustrated by, but by no means limited to, the following 
examples. 
EXAMPLE 1 
This example illustrates a method for the preparation of 
3,5-dimethyl-N-phenyl-4-pyrazolecarboxamide (Compound No 3 of Table I). 
A mixture of acetylacetone (5 g) and triethylamine (5.2 g) in dry benzene 
(50 ml) was treated with phenyl isocyanate (6 g) in dry benzene (25 ml). 
The mixture was stirred for 3 hr at room temperature. Water (50 ml) was 
then added, the mixture shaken and the water layer separated. The benzene 
solution was extracted with two further portions (25 ml) of water and the 
combined aqueous extracts acidified with dilute hydrochloric acid. The 
product precipitated and was collected by filtration, washed with water 
and dried. Diacetyl acetanilide (7.0 g, 73%) was obtained as a colourless 
solid, m.p. 119-121.degree. C. 
The foregoing diacetyl acetanilide (2.2 g) in glacial acetic acid (30 ml) 
was treated with hydrazine hydrate (1.5 g) and the mixture boiled under 
reflux for 30 min. The mixture was then poured into water and the product 
collected and crystallised from ethanol. 
3,5-dimethyl-N-phenyl-4-pyrazolecarboxamide (1.9 g, 86%) was obtained as 
colourless plates, m.p. 244-5.degree. C (Found: C, 66.8 H, 6.0 N, 19.3 
C.sub.12 H.sub.13 N.sub.3 O requires C, 66.9; H, 6.1; N, 19.5%). 
EXAMPLE 2 
This example illustrates a method for the preparation of 
N-cyclohexyl-1,3,5-trimethyl-4-pyrazolecarboxamide (Compound No 28 of 
Table II). 
Ethyl diacetylacetate (Organic Syntheses, Coll. Vol. 3, 1955, p. 309) (51.6 
g) in ethanol (200 ml) was treated with methyl hydrazine (15 g) in 
portions. The mixture was then refluxed gently for 1 hr. About half the 
ethanol was then removed in vacuo and the residue poured into 5% NaCl 
solution (300 ml). The product was extracted with chloroform and the 
chloroform extracts dried and evaporated. The crude 
1,3,5-trimethyl-4-ethoxycarbonylpyrazole was hydrolysed with aqueous 
ethanolic sodium hydroxide solution. The acid (85%) was purified by 
crystallisation from water; it had m.p. 222-3.degree. C (Rojahn and 
Kuhling, Archiv. der Pharmazie (1926), 341; Chem Abs. 20, 2857 (1926), 
give m.p. 217.degree. C for this compound). 
The 1,3,5-trimethyl-4-carboxypyrazole above (3.1 g) was added to thionyl 
chloride (10 ml) and the mixture heated on a steam-bath under reflux and 
protected from moisture for 1 hr. After removal of the excess thionyl 
chloride, cyclohexylamine (2.5 g) in pyridine (20 ml) was added and the 
mixture heated on the steam-bath a further 1 hr. The mixture was then 
poured into 5% hydrochloric acid and the product collected. 
Crystallisation from aqueous ethanol gave 1, 
N-cyclohexyl-1,3,5-trimethyl-4-pyrazolecarboxamide (75% yield), m.p. 185- 
6.degree. C. 
EXAMPLE 3 
By adopting the appropriate procedures and methods similar to those 
described in Examples 1 and 2 above, and using the appropriate reactants 
the specific compounds set out in Table I (excluding that prepared in 
Example I) were prepared. 
EXAMPLE 4 
This example illustrates a method for the preparation of 
1,3-dimethyl-N-(o-tolyl)5-pyrazolecarboxamide (Compound No 30 of Table 
III). 
Ethyl acetopyruvate (Organic Syntheses, Coll. Vol. I, 1944, p. 238) (31.6 
g) was dissolved in ethanol (100 ml) and treated with methyl hydrazine (12 
g) in portions. The mixture was then refluxed gently for 1 hr, whereupon 
most of the ethanol was removed in vacuo. The residue was poured into 5% 
NaCl solution and the product extracted with chloroform (3 .times. 100 
ml). The combined extracts were washed with water, dried and the solvent 
evaporated. The residue was then distilled in vacuo. 
1,3-dimethyl-5-ethoxycarbonylpyrazole (14.5 g 43%) was obtained as a 
colourless oil, b.p..sub. 25 118-121.degree. C. (A mixture of the two 
isomers (1.5 g), followed by pure 1,5-dimethyl-3-ethoxycarbonylpyrazole 
(10.5 g, 31%), b.p..sub. 25 178-180.degree. C, was obtained on continued 
distillation). 
The foregoing 1,3-dimethyl-5-ethoxycarbonylpyrazole (14 g) was hydrolysed 
with aqueous ethanolic sodium hydroxide. The corresponding acid (10.8 g, 
93%) was obtained as a colourless solid m.p. 207-9.degree. C (Elguero et 
al., Bull. Soc. Chim. France (1966), 293; Chem. Abs. 64, 15866(1966), give 
m.p. 207.degree. C for this compound). The acid (3.5 g) was converted to 
the acid chloride by heating with thionyl chloride. After removal of 
excess thionyl chloride in vacuo, the crude acid chloride was treated with 
a mixture of o-toluidine (3 g) in pyridine (20 ml). The mixture was heated 
on a steam-bath for 1 hr, and then poured into 5% hydrochloric acid (200 
ml). The product was filtered and crystallised from aqueous ethanol. 
1,3-dimethyl-N-(o-tolyl)-5-pyrazolecarboxamide (4.9 g, 88%) was obtained 
as colourless needles, m.p. 158-160.degree. C (Found: C, 68.0; H, 6.6; N, 
18.1 C.sub.13 H.sub.15 N.sub.3 O requires: C, 68.1; H, 6.6; N, 18.3%). 
EXAMPLE 5 
By adopting the appropriate procedures and methods similar to that 
described in Example 4 above, and using the appropriate reactants, the 
specific compounds set out in Table III (excluding that prepared in 
Example 4) were prepared. 
EXAMPLE 6 
This example illustrates methods for the preparation of 
5-chloro-1,3-dimethyl-N-phenyl-4-pyrazolecarboxamide 
5-chloro-N-(3-chlorophenyl)-1,3-dimethyl-4-pyrazolecarboxamide 
1,3-dimethyl-N-phenyl-4-pyrazolecarboxamide (Compounds 33, 34 and 35 
respectively, of Table IV). 
(a) 1,3-Dimethylpyrazol-5-one 
Methyl hydrazine (25 g) was added in portions to a solution of ethyl 
acetoacetate (65 g) in ethanol (250 ml). The mixture was refluxed gently 
for 1 hr, whereupon the ethanol was removed in vacuo. The residue was 
crystallised from benzene and 1,3-dimethylpyrazole-5-one (52 g, 93%) was 
obtained as colourless cubic crystals, m.p. 117-119.degree. C. (lit. m.p. 
117.degree. C; Beilstein, Vol. 24, p. 19). 
(b) 4,5-dihydro-1,3-dimethyl-5-oxo-N-phenyl-4-pyrazolecarboxamide 
1,3-Dimethylpyrazole-5-one above (11.2 g) and triethylamine (10.2 g) were 
dissolved in dry benzene and phenyl isocyanate (12 g) added. The mixture 
was stirred 16-18 hrs at room temperature, whereupon it was extracted with 
water (4 .times. 50 ml). The combined aqueous extracts were acidified with 
dilute hydrochloric acid and the mixture refrigerated for several hours. 
The product was then recovered by filtration and dried. 
4,5-dihydro-1,3-dimethyl-5-oxo-N-phenyl-4-pyrazolecarboxamide (17.5 g, 
76%) was obtained as a colourless powder, m.p. 231-233.degree. C. 
From 3-chlorophenyl isocyanate, 
-N-(3-chlorophenyl)-4,5-dihydro-1,3-dimethyl-5-oxo-4-pyrazolecarboxamide 
was similarly obtained in 80% yield, m.p. 242- 243.degree. C. 
(c) 5-chloro-1,3-dimethyl-N-phenyl- 4-pyrazolecarboxamide 
The pyrazolone above (6.9 g) was dissolved in phosphorous oxychloride (30 
ml) and the mixture boiled under reflux for 2 hrs. The mixture was cooled 
and poured into icewater. The product was extracted with chloroform (3 
.times. 50 and the combined extracts were washed with water, dried and 
evaporated. After crystallisation of the crude product from ethanol, 
5-chloro-1,3-dimethyl-N-phenyl-4-pyrazolecarboxamide (3.9 g, 52%) was 
obtained as colourless needles, m.p. 157-159.degree. C. 
5-chloro-N-(3-chlorophenyl)-1,3-dimethyl-4-pyrazolecarboxamide was 
similarly prepared in 67% yield. It crystallised from ethanol as 
colourless crystals, m.p. 161-162.degree. C. 
(d) 1,3-dimethyl-N-phenyl-4-pyrazolecarboxamide 
5-chloro-1,3-dimethyl-N-phenyl-4-pyrazolecarboxamide (2.7 g) was dissolved 
in ethanol (100 ml) and anhydrous sodium acetate (2 g) added. The mixture 
was hydrogenated at room temperature and 2 atmospheres pressure using 
palladium on carbon catalyst. On completion of the reaction, the catalyst 
was removed by filtration through celite and the filtrate evaporated in 
vacuo. Water (50 ml) was added and the product extracted with chloroform 
(3 .times. 25 ml). The combined extracts were washed with water, dried and 
evaporated. The product was crystallised from ethanol and 
1,3-dimethyl-N-phenyl-4-pyrazolecarboxamide (2 g, 96%) was obtained as 
colourless needles, m.p. 91-92.degree. C. 
EXAMPLE 7 
The compounds of this invention were tested in vitro against a wide variety 
of fungal diseases of plants. Inhibition of spore germination and mycelial 
were tested by the standard methods known in the art and the results are 
given in Table V below wherein the codes for the fungi tested have the 
following meanings: 
______________________________________ 
Sn=Septoria nodorum 
Un=Ustilago nuda 
Uf=Uromyces viciae-fabae 
Tf=Tilletia foetida 
CC=Cladosporium cucumerinum 
Mf=Monolinia fructicola 
Pr=Puccinia recondita 
Pc=Phytophthora cinnamomi 
Rs=Rhizoctonia solani 
Gg=Gauemannomyces graminis 
______________________________________ 
TABLE V 
__________________________________________________________________________ 
INHIBITION OF SPORE GERMINATION AND MYCELIAL GROWTH 
Compound 
Spore germination.sup.1 
Mycelial growth.sup.2 
No Sn 
Uf Cc 
Pr Un Tf Mf Pc 
Mf Rs Gg 
__________________________________________________________________________ 
3 ++ + 
5 + 
11 + ++ +++ 
12 + ++ ++ + 
13 + + + ++ +++ +++ 
14 + + ++ +++ +++ 
15 + + + + ++ 
16 + + + ++ + + 
31 ++ + 
32 + 
33 +++ + + 
34 ++ ++ + + + 
35 + + 
__________________________________________________________________________ 
.sup.1 Spore germination 
+++ &gt;50% inhibition of germination at 4 ppm 
++ &gt;50% inhibition of germination at 20 ppm 
+ &gt;50% inhibition of germination at 100 ppm 
.sup.2 Mycelial growth 
+++ &gt;50% of control growth at 3 ppm 
++ &gt;50% of control growth at 10 ppm 
+ &gt;50% of control growth at 30 ppm 
EXAMPLE 8 
The compound of this invention were tested in vivo against Puccinia 
recondita (wheat), Uromyces viciae-fabae (broad beans) and Rhizoctonia 
solani (cotton). The results are shown in Table VI. 
TABLE VI 
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SYSTEMIC AND PROTECTANT ACTIVITY IN VIVO 
Compound 
P. recondita.sup.1 
U. viciae-fabae.sup.2 
R. solani.sup.3 
No Wheat-systemic 
Broad bean-protectant 
cotton 
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3 + 
4 + 
5 ++ 
6 + 
11 + +++* ++ 
12 + ++* +++ 
13 +++ ++* +++ 
14 +++ +++ + 
17 + +++ 
26 ++ 
33 +++ 
34 + 
35 + 
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.sup.1 The compound was applied as a drench to wheat seedlings grown in 
compost (80 c.c. pots) prior to inoculation with P. 
+++ = complete control of infection at the rate of 1 mg/pot 
++ = at the rate of 2 mg/pot 
+ = at the rate of 4 mg/pot 
.sup.2 The compound was applied as a protective spray to broad bean 
seedlings prior to inoculation with spores of U. viciae-fabae 
+++ = infection less than 25% of control at 10 ppm 
++ = infection less than 25% of control at 25 ppm 
+ = infection less than 25% of control at 100 ppm 
*These compounds eradicate U. violae-fabae when sprayed (1000 ppm) onto 
broad bean seedlings 48 hr after inoculation. 
.sup.3 The compound was applied to the soil pre-emergent. After emergence 
the cotton seedlings were inoculated with R. 
+++ = complete protection from infection at a rate of 2 Kg/ha 
+ = complete protection from infection at a rate of 8 Kg/ha 
+ = complete protection from infection at a rate of 16 Kg/ha 
EXAMPLE 9 
Certain of the compounds of this invention were tested in an in vivo 
glass-house trial against Tilletia foetida (wheat bunt). 
In this test wheat seeds were inoculated with spores of T. foetida at 0.5%. 
The seeds were then treated with the test compound and incubated for 3 
weeks at 10.degree. C. The seeds were then potted into 15 cm pots, allowed 
to grow and the plants assessed for disease. The results are shown in 
Table VII. 
TABLE VII 
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IN VIVO 
GLASSHOUSE TRIAL AGAINST TILLETIA FOETIDA 
Compound concentration 
Compound No 
(ppm) Percentage Disease 
______________________________________ 
Control -- 100 
11 250 0 
11 500 0 
13 250 0 
13 500 0 
14 250 0 
14 500 0 
Carboxin 250 0 
Carboxin 500 0 
Control -- 75.8 
33 125 0 
33 250 0 
Fenaminosulf 
100 4 
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EXAMPLE 10 
The compounds and compositions of the invention were tested against a 
variety of fungal diseases of plants. In one test (combined spray/root 
drench) the foliage of the plants was sprayed with a solution of the test 
compound and also the soil in which the plants were growing was drenched 
with another solution of the test compound. Both the solution used for 
spraying and the soil drench solution contained 100 parts per million 
(ppm) of the test compound. 
In another test (root drench) the soil in which the plants were growing was 
drenched with a solution containing 250 ppm of the test compound. 
The plants were infected with the disease it was desired to control before 
or after application of the chemical and after a period of days, depending 
on the particular disease, the extent of the disease was visually 
assessed. The results are given in Table VIII below in the form of a 
grading as follows: 
______________________________________ 
Grading Percentage Amount of Disease 
______________________________________ 
0 61 to 100 
1 26 to 60 
2 6 to 25 
3 0 to 5 
4 0 
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The codes for the fungal disease under test are as follows: 
Pr = Puccinia recondita 
Pi = Phytophthora infestans 
Xo = Xanthomonas oryzae 
Po = Piricularia oryzae 
Rs = Rhizoctonia solani 
Table VIII 
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CONTROL OF PLANT FUNGAL DISEASE BY COMBINED 
SPRAY-ROOT DRENCH AND BY ROOT DRENCH 
Combined Spray/Root Drench 
Root Drench 
Compound 
(100 ppm) (250 ppm) 
No Pr Pi Xo Po Rs 
______________________________________ 
11 4 3 2 
13 4 2 3 1-2 1-2 
15 3 
30 4 2 3 3 
28 3 1-2 1-3 2 
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