O-Alkyl-S-[3-oxo-1,2,4-triazolobenzopyrazin(2)yl-methyl]-(thiono)thiolphosp horic(phosphonic) acid esters of the formula ##STR1## in which R is alkyl with 1 to 4 carbon atoms, PA1 R.sub.1 is alkyl or alkoxy with 1 to 4 carbon atoms, and PA1 X is oxygen or sulfur, Which possess insecticidal properties.

The present invention relates to and has for its objects the provision of 
particular new 
O-alkyl-S-[3-oxo-1,2,4-triazolobenzopyrazin(2)ylmethyl]-(thiono)thiolphosp 
horic(phosphonic) acid esters, which possess insecticidal properties, 
active compositions in the form of mixtures of such compounds with solid 
and liquid dispersible carrier vehicles, and methods for producing such 
compounds and for using such compounds in a new way especially for 
combating pests, e.g. insects, with other and further objects becoming 
apparent from a study of the within specification and accompanying 
examples. 
It is known from German Pat. Nos. 2,758,115, 2,759,010 and 2,791,599 that 
O,O-dialkylthiolphosphoric acid esters, for example 
O,O-dimethyl-S-(ethylthioethyl- (Compound A) and 
-ethylthionylethyl)-thiolphosphoric acid esters (Compound B) and 
O,O-diethyl-S-[4-oxo-1,2,3-benzotriazin-3(4H)ylmethyl]-thionothiolphosphor 
ic acid ester (Compound C), have insecticidal properties. 
The present invention provides, as new compounds, the 
S-triazolobenzopyrazinemethyl(thiono)thiolphosphoric(phosphonic) acid 
esters of the general formula 
##STR2## 
in which R is alkyl with 1 to 4 carbon atoms, 
R.sub.1 is alkyl or alkoxy with 1 to 4 carbon atoms, and 
X is oxygen or sulfur. 
Preferably, R is straight-chain or branched alkyl with 1 to 3 (especially 1 
or 2 ) carbon atoms, R.sub.1 is straight-chain or branched alkyl or alkoxy 
each with 1 to 3 (especially 1 or 2) carbon atoms, and X is sulfur. 
Surprisingly, the 
S-triazolobenzopyrazinemethyl(thiono)thiolphosphoric(phosphonic) acid 
esters according to the present invention show a better insecticidal 
action than the previously known compounds of the same type of action. The 
compounds according to the invention thus represent a genuine enrichment 
of the art. 
The invention also provides a process for the preparation of an 
S-triazolobenzopyrazinemethyl(thiono)thiolphosphoric(phosphonic) acid 
ester of the formula (I) in which a (thiono)thiolphosphoric(phosphonic) 
acid ester of the general formula 
##STR3## 
in which R, R.sub.1 and X have the above-mentioned meanings, and 
M is hydrogen or one equivalent of an alkali metal, alkaline earth metal or 
ammonium, 
is reacted with a 2-halogenomethyl-3-oxo-(1,2,4-triazolobenzopyrazine) of 
the general formula 
##STR4## 
in which Hal is halogen, 
if appropriate in the presence of an acid acceptor and optionally in the 
presence of a solvent or diluent. 
A 2-halogenomethyl-3-oxo-1,2,4-triazolobenzopyrazine to be used as the 
starting material can be obtained in accordance with generally customary 
methods, by converting the known-2-hydroxy-benzopyrazine into 
2-chloro-benzopyrazine, converting the latter into the hydrazino 
derivative by means of hydrazine hydrate, and subsequently into the 
2-ethoxycarbonylhydrazino derivative. Cyclization in alkaline solution is 
then carried out, followed by reaction with formaldehyde to give 
2-hydroxymethyl-3-oxo-1,2,4-triazolobenzopyrazine and halogenation of the 
latter, in accordance with the following equations: 
##STR5## 
The following may be mentioned as examples of the 
2-halogenomethyl-3-oxo-1,2,4-triazolobenzopyrazines to be employed in 
accordance with the process: 2-chloromethyl- and 
2-bromomethyl-3-oxo-1,2,4-triazolobenzopyrazine. 
If, for example, the potassium salt of O-ethyl-thionothiolethanephosphonic 
acid ester and 2-chloromethyl-3-oxo-1,2,4-triazolobenzopyrazine are 
employed as starting materials, the course of the reaction can be 
represented by the following equation: 
##STR6## 
The (thiono)thiolphosphoric(phosphonic) acid esters (II) to be used as 
starting materials are known from the literature and can be prepared in 
accordance with generally customary processes. 
As examples of these compounds there may be mentioned: O,O-dimethyl-, 
O,O-diethyl-, O,O-di-isopropyl-, O,O-di-n-propyl-, O-ethyl-O-n-propyl-, 
O-ethyl-O-isopropyl- and O-methyl-O-ethylthiolphosphoric acid diesters, 
the corresponding alkali metal salts, alkaline earth metal salts and 
ammonium salts and, in each case, the corresponding thiono analogues, and 
also O-methyl-, O-ethyl-, O-n-propyl- and O-isopropyl- methane-, -ethane-, 
-n-propane- and -isopropane-thiolphosphonic acid esters, the corresponding 
alkali metal salts, alkaline earth metal salts and ammonium salts and, in 
each case, the corresponding thiono analogues. 
The process for the preparation of the compounds according to the invention 
is preferably carried out in the presence of a suitable solvent or 
diluent. Practically all inert organic solvents can be employed for this 
purpose, especially aliphatic and aromatic, optionally chlorinated, 
hydrocarbons, such as benzene, toluene, xylene, benzine, methylene 
chloride, chloroform, carbon tetrachloride and chlorobenzene; ethers, for 
example diethyl ether, dibutyl ether and dioxane; ketones, for example 
acetone, methyl ethyl ketone, methyl isopropyl ketone and methyl isobutyl 
ketone; and nitriles, such as acetonitrile and propionitrile. 
All customary acid-binding agents can be used as the acid acceptors. Alkali 
metal carbonates and alkali metal alcoholates, such as sodium carbonate, 
methylate and ethylate and potassium carbonate, methylate and ethylate, 
have proved particularly suitable, as have aliphatic, aromatic or 
heterocyclic amines, for example triethylamine, trimethylamine, 
dimethylaniline, dimethylbenzylamine and pyridine. 
The reaction temperature can be varied within a fairly wide range. In 
general, the reaction is carried out at between 0.degree. and 120.degree. 
C, preferably at from 40.degree. to 50.degree. C. 
The reaction is in general allowed to take place under normal pressure. 
To carry out the process, the 
2-halogenomethyl-3-oxo-1,2,4-triazolobenzopyrazine is preferably employed 
in 10 to 20% excess. In most cases, the (thiono)thiolphosphoric 
(phosphonic) acid ester component is employed in the form of a salt. After 
bringing the components together, preferably in a solvent or diluent, the 
reaction solution is stirred at an elevated temperature for one or more 
hours. After completion of the reaction, the solution is filtered while 
still warm, the solvent is distilled off and water is added to the 
residue. In some cases, the substance which separates out can be filtered 
off directly; in other cases, the aqueous phase is extracted by shaking 
with an organic solvent, for example toluene, and the organic layer is 
worked up in the usual manner by washing, drying and distillation. Most 
substances are obtained in a crystalline form and are characterized by 
their melting point. Some are obtained in the form of oils which in most 
cases cannot be distilled without decomposition but are freed from the 
last volatile constituents by so-called "slight distillation", that is to 
say by prolonged heating to moderately elevated temperatures under reduced 
pressure, and are purified in this way. They are characterized by the 
refractive index. 
As has already been mentioned, the 
S-triazolobenzopyrazinemethyl(thiono)thiolphosphoric(phosphonic) acid 
esters according to the invention are distinguished by an excellent 
insecticidal activity. They are active not only against leaf insects and 
soil insects and against pests harmful to health and pests of stored 
products, but also, in the veterinary medicine field, against animal 
parasites (ectoparasites), such as parasitic fly larvae. They combine a 
low phytotoxicity with a good action against both sucking and biting 
insects. 
For this reason, the compounds according to the invention can be employed 
successfully as pesticides in plant protection as well as in the hygiene 
field, the field of protection of stored products and the veterinary 
field. 
To the sucking insects there belong, in the main, aphids (Aphididae) such 
as the green peach aphid (Myzus persicae), the bean aphid (Doralis fabae), 
the bird cherry aphid (Rhopalosiphum padi), the pea aphid (Macrosiphum 
pisi) and the potato aphid (Macrosiphum solanifolii), the currant gall 
aphid (Cryptomyzus korschelti), the mealy apple aphid (Sappaphis mali), 
the mealy plum aphid (Hyalopterus arundinis) and the cherry black-fly 
(Myzus cerasi); in addition, scales and mealybugs (Coccina), for example 
the oleander scale (Aspidiotus hederae) and the soft scale (Lecanium 
hesperidum) as well as the grape mealybug (Pseudococcus maritimus); thrips 
(Thysanoptera), such as Hercinothrips femoralis, and bugs, for example the 
beet bug (Piesma quadrata), the cotton bug (Dysdercus intermedius), the 
bed bug (Cimex lectularius), the assassin bug (Rhodnius prolixus) and 
Chagas' bug (Triatoma infestans) and, further, cicadas, such as Euscelis 
bilobatus and Nephotettix bipunctatus. 
In the case of the biting insects, above all there should be mentioned 
butterfly caterpillars (Lepidoptera) such as the diamond-back moth 
(Plutella maculipennis) the gypsy moth (Lymantria dispar), the brown-tail 
moth (Euproctis chrysorrhoea) and tent caterpillar (Malacosoma neustria); 
further, the cabbage moth (Mamestra brassicae) and the cutworm (Agrotis 
segetum), the large white butterfly (Pieris brassicae), the small winter 
moth (Cheimatobia brumata), the green oak tortrix moth (Tortrix viridana), 
the fall armyworm (Laphygma frugiperda) and cotton worm (Prodenia litura), 
the ermine moth (Hyponomeuta padella), the Mediterranean flour moth 
(Ephestia kuhniella) and greater wax moth (Galleria mellonella). 
Also to be classed with the biting insects are beetles (Coleoptera), for 
example the granary weevil (Sitophilus granarius = Calandra granaria), the 
Colorado beetle (Leptinotarsa decemlineata), the dock beetle (Gastrophysa 
viridula), the mustard beetle (Phaedon cochleariae), the blossom beetle 
(Meligethes aeneus), the raspberry beetle (Byturus tomentosus), the bean 
weevil (Bruchidius = Acanthoscelides obtectus), the leather beetle 
(Dermestes frischi), the khapra beetle (Trogoderma granarium), the flour 
beetle (Tribolium castaneum), the northern corn billbug (Calandra or 
Sitophilus zeamais), the drugstore beetle (Stegobium paniceum), the yellow 
mealworm (Tenebrio molitor) and the saw-toothed grain beetle (Oryzaephilus 
surinamensis), and also species living in the soil, for example wireworms 
(Agriotes spec.) and larvae of the cockchafer (Melolontha melolontha); 
cockroaches, such as the German cockroach (Blattella germanica), American 
cockroach (Periplaneta americana), Madeira cockroach (Leucophaea or 
Rhyparobia maderae), Oriental cockroach (Blatta orientalis), the giant 
cockroach (Blaberus giganteus) and the black giant cockroach (Blaberus 
fuscus) as well as Henschoutedenia flexivitta; further, Orthoptera, for 
example the house cricket (Gryllus domesticus); termites such as the 
eastern subterranean termite (Reticulitermes flavipes) and Hymenoptera 
such as ants, for example the garden ant (Lasius niger). 
The Diptera comprise essentially the flies, such as the vinegar fly 
(Drosophila melanogaster), the Mediterranean fruit fly (Ceratitis 
capitata), the house fly (Musca domestica), the little house fly (Fannia 
canicularis), the black blow fly (Phormia regina) and bluebottle fly 
(Calliphora erythrocephala) as well as the stable fly (Stomoxys 
calcitrans); further, gnats, for example mosquitoes such as the yellow 
fever mosquito (Aedes aegypti), the northern house mosquito (Culex 
pipiens) and the malaria mosquito (Anopheles stephensi). 
The active compounds according to the instant invention can be utilized, if 
desired, in the form of the usual formulations or compositions with 
conventional inert (i.e. plant compatible or herbicidally inert) pesticide 
diluents or extenders, i.e. diluents, carriers or extenders of the type 
usable in conventional pesticide formulations or compositions, e.g. 
conventional pesticide dispersible carrier vehicles such as gases, 
solutions, emulsions, suspensions, emulsifiable concentrates, spray 
powders, pastes, soluble powders, dusting agents, granules, etc. These are 
prepared in known manner, for instance by extending the active compounds 
with conventional pesticide dispersible liquid diluent carriers and/or 
dispersible solid carriers optionally with the use of carrier vehicle 
assistants, e.g. conventional pesticide surface-active agents, including 
emulsifying agents and/or dispersing agents, whereby, for example, in the 
case where water is used as diluent, organic solvents may be added as 
auxiliary solvents. The following may be chiefly considered for use as 
conventional carrier vehicles for this purpose: aerosol propellants which 
are gaseous at normal temperatures and pressures, such as Freon; inert 
dispersible liquid diluent carriers, including inert organic solvents, 
such as aromatic hydrocarbons (e.g benzene, toluene, xylene, alkyl 
naphthalenes, etc.), halogenated, especially chlorinated, aromatic 
hydrocarbons (e.g. chlorobenzenes, etc.), cycloalkanes, (e.g. cyclohexane, 
etc.), paraffins (e.g. petroleum or mineral oil fractions), chlorinated 
aliphatic hydrocarbons (e.g. methylene chloride, chloroethylenes, etc.), 
alcohols (e.g. methanol, ethanol, propanol, butanol, glycol, etc.) as well 
as ethers and esters thereof (e.g. glycol monomethyl ether, etc.), amines 
(e.g. ethanolamine, etc.), amides (e.g. dimethyl formamide, etc.), 
sulfoxides (e.g. dimethyl sulfoxide, etc.), acetonitrile, ketones (e.g. 
acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 
etc.), and/or water; as well as inert dispersible finely divided solid 
carriers, such as ground natural minerals (e.g. kaolins, clays, alumina, 
silica, chalk, i.e. calcium carbonate, talc, attapulgite, montmorillonite, 
kieselguhr, etc.) and ground synthetic minerals (e.g. highly dispersed 
silicic acid, silicates, e.g. alkali silicates, etc.); whereas the 
following may be chiefly considered for use as conventional carrier 
vehicle assistants, e.g. surface-active agents, for this purpose: 
emulsifying agents, such as non-ionic and/or anionic emulsifying agents 
(e.g. polyethylene oxide esters of fatty acids, polyethylene oxide ethers 
of fatty alcohols, alkyl sulfates, alkyl sulfonates, aryl sulfonates, 
albumin hydrolyzates, etc., and especially alkyl arylpolyglycol ethers, 
magnesium stearate, sodium oleate, etc.); and/or dispersing agents, such 
as lignin, sulfite waste liquors, methyl cellulose, etc. 
Such active compounds may be employed alone or in the form of mixtures with 
one another and/or with such solid and/or liquid dispersible carrier 
vehicles and/or with other known compatible active agents, especially 
plant protection agents, such as other insecticides, or acaricides, 
nematocides, fungicides, bactericides, rodenticides, herbicides, 
fertilizers, growth-regulating agents, etc., if desired, or in the form of 
particular dosage preparations for specific application made therefrom, 
such as solutions, emulsions, suspensions, powders, pastes, and granules 
which are thus ready for use. 
As concerns commercially marketed preparations, these generally contemplate 
carrier composition mixtures in which the active compound is present in an 
amount substantially between about 0.1-95% by weight, and preferably 
0.5-90% by weight, of the mixture, whereas carrier composition mixtures 
suitable for direct application or field application generally contemplate 
those in which the active compound is present in an amount substantially 
between about 0.0001-10%, preferably 0.01-1%, by weight of the mixture. 
Thus, the present invention contemplates overall compositions which 
comprise mixtures of a conventional dispersible carrier vehicle such as 
(1) a dispersible inert finely divided carrier solid, and/or (2) a 
dispersible carrier liquid such as an inert organic solvent and/or water, 
preferably including a surface-active effective amount of a carrier 
vehicle assistant, e.g. a surface-active agent, such as an emulsifying 
agent and/or a dispersing agent, and an amount of the active compound 
which is effective for the purpose in question and which is generally 
between about 0.0001-95%, and preferably 0.01-95%, by weight of the 
mixture. 
The active compounds can also be used in accordance with the well known 
ultra-low-volume process with good success, i.e. by applying such compound 
if normally a liquid, or by applying a liquid composition containing the 
same, via very effective atomizing equipment, in finely divided form, e.g. 
average particle diameter of from 50-100 microns, or even less, i.e. mist 
form, for example by airplane crop spraying techniques. Only up to at most 
about a few liters/hectare are needed, and often amounts only up to about 
15 to 1000 g/hectare, preferably 40 to 600 g/hectare, are sufficient. In 
this process it is possible to use highly concentrated liquid compositions 
with said liquid carrier vehicles containing from about 20 to about 95% by 
weight of the active compound or even the 100% active substance alone, 
e.g. about 20-100% by weight of the active compound. 
Furthermore, the present invention contemplates methods of selectively 
killing, combating or controlling pests, e.g. insects, which comprises 
applying to at least one of correspondingly (a) such insects, and (b) the 
corresponding habitat thereof, i.e. the locus to be protected, e.g. to a 
growing crop, to an area where a crop is to be grown or to a domestic 
animal, a correspondingly combative or toxic amount, i.e. an 
insecticidally effective amount, of the particular active compound of the 
invention alone or together with a carrier vehicle as noted above. The 
instant formulations or compositions are applied in the usual manner, for 
instance by spraying, atomizing, vaporizing, scattering, dusting, 
watering, squirting, sprinkling, pouring, fumigating, dressing, 
encrusting, and the like. 
It will be realized, of course, that the concentration of the particular 
active compound utilized in admixture with the carrier vehicle will depend 
upon the intended application. Therefore, in special cases it is possible 
to go above or below the aforementioned concentration ranges.

The unexpected superiority and outstanding activity of the particular new 
compounds of the present invention are illustrated, without limitation, by 
the following examples: 
EXAMPLE 1 
Phaedon Larvae test 
Solvent: 3 parts by weight of acetone 
Emulsifier: 1 part by weight of alkylaryl polyglycol ether 
To produce a suitable preparation of active compound, 1 part by weight of 
the active compound was mixed with the stated amount of solvent containing 
the stated amount of emulsifier and the concentrate was diluted with water 
to the desired concentration. 
Cabbage plants (Brassica oleracea) were sprayed with the preparation of the 
active compound until dripping wet and were then infested with mustard 
beetle larvae (Phaedon cochleariae). 
After the specified periods of time, the degree of destruction was 
determined in %: 100% means that all of the beetle larvae had been killed 
whereas 0% means that none of the beetle larvae has been killed. 
The active compounds, the concentrations of the active compounds, the 
evaluation times and the results can be seen from the following table: 
Table 1 
__________________________________________________________________________ 
(Phaedon larvae test) 
Degree of 
Active com- 
destruc- 
pound con- 
tion in % 
centration 
after 3 
Active compound in % days 
__________________________________________________________________________ 
##STR7## 0.1 0.01 0.001 
100 100 0 
##STR8## 0.1 0.01 0.001 
100 100 0 
##STR9## 0.1 0.01 0.001 
100 100 100 
##STR10## 0.1 0.01 0.001 
100 100 90 
##STR11## 0.1 0.01 0.001 
100 100 95 
__________________________________________________________________________ 
EXAMPLE 2 
Plutella test 
Solvent: 3 parts by weight of acetone 
Emulsifier: 1 part by weight of alkylaryl polyglycol ether 
To produce a suitable preparation of active compound, 1 part by weight of 
the active compound was mixed with the stated amount of solvent containing 
the stated amount of emulsifier and the concentrate was diluted with water 
to the desired concentration. 
Cabbage leaves (Brassica oleracea) were sprayed with the preparation of the 
active compound until dew moist and were then infested with caterpillars 
of the diamond-back moth (Plutella maculipennis). 
After the specified period of time, the degree of destruction was 
determined as a percentage: 100% means that all the caterpillars were 
killed whereas 0% means that none of the caterpillars were killed. 
The active compounds, the concentrations of the active compounds, the 
evaluation times and the results can be seen from the following table: 
Table 2 
__________________________________________________________________________ 
(Plutella test) 
Degree of 
Active com- 
destruc- 
pound con- 
tion in % 
centration 
after 3 
Active compound in % days 
__________________________________________________________________________ 
##STR12## 0.1 0.01 
100 0 
(known) (A) 
##STR13## 0.1 0.01 
100 0 
(known) (B) 
##STR14## 0.1 0.01 
100 100 
(3) 
##STR15## 0.1 0.01 
100 100 
(1) 
##STR16## 0.1 0.01 
100 100 
(2) 
##STR17## 0.1 0.01 
100 100 
(4) 
__________________________________________________________________________ 
EXAMPLE 3 
Critical concentration test/soil insects 
Test insect: Phorbia antigua grubs in the soil 
Solvent: 3 parts by weight of acetone 
Emulsifier: 1 part by weight of alkylaryl polyglycol ether 
To produce a suitable preparation of active compound, 1 part by weight of 
active compound was mixed with the stated amount of solvent, the stated 
amount of emulsifier was added and the concentrate was diluted with water 
to the desired concentration. 
The preparation of active compound was intimately mixed with the soil. The 
concentration of the active compound in the preparation was practically 
immaterial, the only decisive factor being the amount by weight of active 
compound per unit volume of soil, which is quoted in ppm (= mg/1). The 
soil was filled into pots and the pots were left to stand at room 
temperature. 
After 24 hours the test insects were introduced into the treated soil and 
after a further 2 to 7 days the degree of effectivenes of the active 
compound was determined in % by counting the dead and live test insects. 
The degree of effectiveness is 100% if all test insects has been killed 
and is 0% if exactly as many test insects were still alive as in the case 
of the untreated control. 
The active compounds, amounts used and results can be seen from the table 
which follows: 
Table 3 
______________________________________ 
(Soil insecticide test/Phorbia antiqua grubs 
in the soil) 
Degree of 
destruction 
in % at an 
active com- 
pound con- 
centration 
Active compound of 20 ppm 
______________________________________ 
##STR18## 0 
(known) (A) 
##STR19## 0 
(known) (B) 
##STR20## 100 
(2) 
##STR21## 100 
(4) 
______________________________________ 
EXAMPLE 4 
Critical concentration test/soil insects 
Test insect: Tenebrio molitor larvae in the soil 
Solvent: 3 parts by weight of acetone 
Emulsifier: 1 part by weight of alkylaryl polyglycol ether 
To produce a suitable preparation of active compound, 1 part by weight of 
active compound was mixed with the stated amount of solvent, the stated 
amount of emulsifier was added and the concentrate was diluted with water 
to the desired concentration. 
The preparation of active compound was intimately mixed with the soil. The 
concentration of the active compound in the preparation was practically 
immaterial, the only decisive factor being the amount by weight of active 
compound per unit volume of soil, which is quoted in ppm (= mg/1). The 
soil was filled into pots and the pots were left to stand at room 
temperature. 
After 24 hours the test insects were introduced into the treated soil and 
after a further 2 to 7 days the degree of effectiveness of the active 
compound was determined in % by counting the dead and live test insects. 
The degree of effectiveness is 100% if all the test insects had been 
killed and is 0% if exactly as many test insects were still alive as in 
the case of the untreated control. 
The active compounds, amounts used and results can be seen from the table 
which follows: 
Table 4 
______________________________________ 
(Soil insecticide test/Tenebrio molitor larvae in the soil) 
Degree of des- 
truction in % 
at an active 
compound con- 
centration of 
Active compound 20 ppm 
______________________________________ 
##STR22## 50 
##STR23## 0 
##STR24## 0 
##STR25## 100 
##STR26## 100 
______________________________________ 
EXAMPLE 5 
Test with parasitic fly larvae 
Solvent: 
35 parts by weight of ethylene polyglycol monomethyl ether 
35 parts by weight of nonylphenol polyglycol ether 
To produce a suitable preparation of active compound, 30 parts by weight of 
the active substance in question were mixed with the stated amount of 
solvent which contained the above-mentioned proportion of emulsifier and 
the concentrate thus obtained was diluted with water to the desired 
concentration. 
About 20 fly larvae (Lucilia cuprina res.) were introduced into a test tube 
which contained approximately 2 cm.sup.3 of horse muscle. 0.5 ml of the 
preparation of active compound was applied to this horse meat. After 24 
hours, the degree of destruction in % was determined. 100% means that all 
the larvae had been killed and 0% means that no larvae had been killed. 
The active compounds investigated, the concentrations of the active 
compounds used and the results obtained can be seen from the table which 
follows: 
Table 5 
__________________________________________________________________________ 
(Test with parasitic fly larvae/Lucilia cuprina res.) 
Active com- 
pound con- 
Degree of 
centration 
destruc- 
Active compound in ppm tion in % 
__________________________________________________________________________ 
##STR27## 100 10 
100 100 
##STR28## 100 30 10 1 
100 100 100 100 
##STR29## 100 10 1 
100 100 100 
##STR30## 100 30 10 
100 100 100 
##STR31## 100 10 1 
100 100 100 
__________________________________________________________________________ 
The process of this invention is illustrated by the following preparative 
Examples. 
EXAMPLE 6 
##STR32## 
A mixture of 74 g (0.5 mole) of 2-hydroxy-benzopyrazine, 12 g of 
dimethylaniline and 250 ml of phosphorus oxychloride was heated under 
reflux for 10 minutes. At about 80.degree. C, all the material had 
dissolved; the reaction solution was cooled and poured onto ice, and the 
product was filtered off. The residue was dried on clay and was then taken 
up in petroleum ether, and the solution was filtered through active 
charcoal. The reaction solution was evaporated and 78 g (87.5% of theory) 
of 2-chloro-benzopyrazine of melting point 48.degree.-49.degree. C, were 
obtained. 
##STR33## 
165 g (1 mole) of the substance described under (a) were added to a mixture 
of 400 ml of absolute ethanol and 400 ml of hydrazine hydrate and the 
reaction temperature was kept at 40.degree. C by slight cooling. The 
mixture was stirred for a further 3 hours and the precipitate was filtered 
off and washed with water. 137 g (85.5% of the theory) of 
2-hydrazino-benzopyrazine, of melting point 162.degree. C (decomposition) 
were obtained as an orange-colored powder. 
##STR34## 
152 g (0.96 mole) of pyrocarbonic acid diethyl ester were added to 128 g 
(0.8 mole) of 2-hydrazino-benzopyrazine in 2 l of dry ethanol and the 
reaction solution was kept at 35.degree. C by slight cooling. After the 
evolution of CO.sub.2 had ended, a product crystallized out. The reaction 
mixture was stirred for a further 30 minutes and the product was then 
filtered off. 165 g (88.5% of theory) of 
2-(2'-ethoxycarbonylhydrazino)-benzopyrazine were obtained as a yellow 
powder of decomposition point 180.degree.-190.degree. C. 
##STR35## 
138 g (0.6 mole) of the substance prepared under (c) were added to 265 g 
(0.66 mole) of sodium hydroxide in 660 ml of water. The reaction mixture 
was left to stand on a waterbath for 3 hours at 80.degree. C. The turbid 
solution was filtered hot, cooled and acidified and the precipitate was 
filtered off. 101 g (90% of theory) of 
3-oxo-1,2,4-triazolo-2H-benzopyrazine of melting point 298.degree. C were 
obtained as a yellow, non-crystallizable powder. 
##STR36## 
A mixture of 560 ml of formaldehyde and 93 g of 
3-oxo-1,2,4-triazolo-2H-benzopyrazine was warmed on a water bath. The 
mixture thickened initially and then again became somewhat less viscous. 
The reaction mixture was left to stand for 2 hours at 80.degree. C and was 
then cooled, and the precipitate was filtered off and washed with water. 
99 g (91.5% of theory) of 
2-hydroxymethyl-3-oxo-1,2,4-triazolo-benzopyrazine were obtained as a 
yellow powder of melting point 204.degree. C (decomposition). 
##STR37## 
68.5 g (0.48 mole; 42 ml) of thionyl chloride were added to a mixture of 
86.5 g (0.4 mole) of 2-hydroxymethyl-3-oxo-1,2,4-triazolo-benzopyrazine in 
400 ml of methylene chloride and 2 ml of dimethylformamide, while keeping 
the reaction temperature at 35.degree. C by slight cooling. After stirring 
for 2 hours, the reaction mixture was subjected to distillation and water 
was added to the residue. The aqueous solution was rendered neutral with 
sodium bicarbonate and the product was filtered off. This gave 90 g (95.5% 
of theory) of 2-chloromethyl-3-oxo-1,2,4-triazol benzopyrazine of melting 
point 178.degree. C. The yellow crystals could be recrystallized from 
acetonitrile. 
##STR38## 
70 g (0.3 mole) of 2-chloromethyl-3-oxo-1,2,4-triazolobenzopyrazine were 
added to 57 g (0.36 mole) of the ammonium salt of 
O,O-dimethylthiolphosphoric acid ester in 350 ml of acetonitrile and the 
reaction solution was stirred for 2 hours at 50.degree. C. The solution 
was filtered while warm, the solvent was distilled off and water was added 
to the residue. The mixture was again filtered, the product was 
recrystallized from acetone and 32 g (31.5% of theory) of 
O,O-dimethyl-S-[3-oxo-1,2,4-triazolobenzopyrazin(2)ylmethyl]-thiolphosphor 
ic acid ester were obtained in the form of fine yellow crystals of melting 
point 125.degree. C. 
EXAMPLE 7 
##STR39## 
70 g (0.3 mole) of 2-chloromethyl-3-oxo-1,2,4-triazolobenzopyrazine were 
added to 73 g (0.36 mole) of the ammonium salt of 
O,O-diethylthionothiolphosphoric acid diester, dissolved in 300 ml of 
acetone; there was no exothermic effect. After stirring for one hour at 
50.degree. C, the reaction mixture was cooled and filtered, and the 
solvent was distilled off. Water was added to the residue and the product 
was filtered off and taken up in toluene. The organic phase was dried and 
the solvent was distilled off. 97 g (84% of theory) of 
O,O-diethyl-S-[3-oxo-1,2,4-triazolobenzopyrazine(2)ylmethyl]-thionothiolph 
osphoric acid ester were obtained. The substance was recrystallized from 
acetonitrile; yellow needles of melting point 100.degree. C were obtained. 
The following compounds can be prepared by analogous procedures: 
__________________________________________________________________________ 
Physical data 
(melting point 
[.degree. C]; refractive 
Yield 
Compound No. 
Structure index) (% of theory) 
__________________________________________________________________________ 
(3) 
##STR40## 123 60.5 
(4) 
##STR41## 122 80 
(5) 
##STR42## n.sub.D.sup.21 : 1.5890 
45 
__________________________________________________________________________ 
It will be appreciated that the instant specification and examples are set 
forth by way of illustration and not limitation, and that various 
modifications and changes may be made without departing from the spirit 
and scope of the present invention.