The action o [" salt.; of N-monosubstituted ['4-methyl-3-methyl(ao,l)-2-thiooxy-l,3-thiazolyl-5-carboxylic acids, which can be converted to the corresponding acid, acid chloride, and anilide.

Treatment of 3,4-dimethyl-2-thioxothiazoline-5-carboxylic acid hydrazide with NH 4 SCN and PhCONCSgave the corresponding thiosemicarbazides, arylsulfochlorides yielded the arylsulfonylhydrazides, and diazotization conditions gave the corresponding azide. The interactions of the latter with different nucleophiles have been studied and a series of novel carbamic acid, urea, and semicarbazide derivatives containing a thiazoline fragment have been prepared.In continuation of our search for a novel series of biologically active substances based on the previously reported 3,4-dimethyl-2-thioxothiazoline-5-carboxylic acid hydrazide (1) [1] we now report the preparation of its arylsulfonyl and thiocarbamoyl derivatives 2a-e and 3, 4 respectively as well as the azide product of its diazotization 5. Compounds 2a-e are related in structure to known sulfonylamides [2] or thiourea derivatives [3] and hence attract particular interest as potential medicinal agents and pesticides. The azide 5, being a thiazolineisocyanate donor under Curtius reaction conditions can serve as a valuable starting compound for the development of novel routes to functionalize a thiazoline system and this has been demonstrated in a series of examples.When treated with arylsulfochlorides in pyridine medium at 20°C the hydrazide 1 gave high yields (80-90%) of the arylsulfonylhydrazides 2a-e and when refluxed with ammonium thiocyanate in ethanol or with benzoylisothiocyanate in dioxane the thiosemicarbazide 3 (yield 61%) or benzoylthiosemicarbazide 4 (yield 78%) respectively (Scheme 1).A single unsuccessful attempt to carry out the reaction of thiazolecarboxylic acid hydrazides to the corresponding azide has been reported in the literature. In [3] it was shown that 2-substituted 5-phenylthiazolecarboxylic acid hydrazides in excess acetic acid and the presence of NaNO 2 underwent a more extensive reaction and, in place of the expected azides, gave the N,N'-bis(2-substituted-5-phenyl)thiazolylureas.Despite this data we have found in our work that hydrazide 1 readily forms the azide 5 when treated with an equimolar amount of HNO 2 in aqueous medium in 91% yield. The reactions of the azide with various nucleophiles have been studied. It was found that, at 100-120°C in absolute toluene, the azide indicated underwent a Curtius rearrangement reaction to the corresponding isocyanate which reacts with alcohols, amines, and hydrazides to form novel derivatives of carbamic acid 6a-g, urea 7a-k, and semicarbazide 8a-d containing a thiazoline fragment.

We have studied the temperature dependence of the 1 H NMR spectra of some 2,4,6-trisubstituted 1,3,5-triazines having an NHAlk or NAlk 2 group or groups at the position 2 or 2 and 4 of the heterocycle. We have shown that rotation of these groups about the C-N bond is hindered. We have calculated the free energies of activation for the rotation processes.Keywords: 2,4,6-trisubstituted 1,3,5-triazines, hindered internal rotation, isomers, free energy of activation.In the 1 H NMR spectra of triazine derivatives containing NHAlk or NAlk 2 substituents at the positions 2 and 4 of the heterocycle, we observed two or more sets of signals from protons of the N-alkyl and NH groups which may be connected with the presence in the solutions of different isomeric forms of the indicated compounds [1]. In order to study this question, we recorded the 1 H NMR spectra of trisubstituted triazines 1-3 in the temperature range 20-90°C. 1 a R 1 = R 2 = NMe 2 , R 3 = Cl; b R 1 = NMe 2 , R 2 = OMe, R 3 = Cl; c R 1 = NHMe, R 2 = OMe, R 3 = Cl; d R 1 = R 2 = NHEt, R 3 = CN; e R 1 = R 2 = NHCHMe 2 , R 3 = CN; f R 1 = NHEt, R 2 = NHCMe 3 , R 3 = Cl; g R 1 = NMe 2 , R 2 = OMe, R 3 = OC 6 H 4 COOEt-p; h R 1 = NHEt, R 2 = SMe, R 3 = OC 6 H 4 COOEt-p; i R 1 = R 2 = NHCHMe 2 , R 3 = OC 6 H 4 COOMe-p; 2 a R 1 = R 2 = NMe 2 , R 3 = OH; b R 1 = NMe 2 , R 2 = OMe, R 3 = OH; c R 1 = NHEt, R 2 = OMe, R 3 = OH; d R 1 = NHEt, R 2 = OMe, R 3 = OCHMe 2 ; e R 1 = R 2 = NHEt, R 3 = OH; f R 1 = R 2 = NHEt, R 3 = OEt; g R 1 = R 2 = NHCHMe 2 , R 3 = OH; h R 1 = R 2 = NHCHMe 2 , R 3 = OMe; 3 a R 1 = R 2 = NMe 2 ; b R 1 = NMe 2 , R 2 = OMe; c R 1 = NHEt, R 2 = OMe; d R 1 = R 2 = NHEt; e R 1 = R 2 = NHCHMe 2 ; a-e R 3 = Me __________________________________________________________________________________________ Armenian Agricultural Academy, Yerevan 375009;

A convenient method for synthesis of novel 1- [pyrimidinyl], 1-[1,3,5-triazin-2-carbonyl], and 1-[thiazol-5-carbonyl] derivatives of 3-thioxo-diaziridine 1, 3, 5, and 7 from corresponding hydrazides, CS2, and KOH is elaborated. The highest reaction yield was observed when these initial reagents were taken in molar ratio of 1:1.7:2.0, respectively. By alkylation of compounds 1, 3, 5, and 7 that proceeds exclusively at sulfur atom, the 3-sulfanyl derivatives of 1-[pyrimidinyl]-, 1-[1,3,5-triazin-2-carbonyl]-, and 1-[thiazol-5-carbonyl]-diazirines 2, 4, 6, and 8 were formed. The structures of synthesized compounds were confirmed by proton and carbon nuclear magnetic resonance (NMR), mass spectra (MS), and elemental analysis. The fungicidal activities of S-substituted derivatives were studied. Data of preliminary biological tests testify that these compounds can be of interest in search for new fungicides.

No abstract