The synthesis of substituted 1,3,4-oxadiazol, 1,2,4-triazol and Schiff base from chalcones has been achieved. Mercapto acetic acid was reacted with the chalcone compound (1) to form carboxylic acid (2). Esterification of compound (2) has been accomplished through acidic conditions to give compound

Synthesis Of 2-Benzamidomethyl-5-Substituted Amino-1,3,4-Thiadiazoles-2,5-… 28 anhydride. Oxazolinone (3,4) were treated with hydrazine hydrate to give acid hydrazides (5,6). Acid hydrazides were converted to substituted thiosemi-carbazides (7,8) by their reaction with phenyl isothiocyanate. Substituted thiosemicarbazides (7,8) were treated with sodium hydroxide and concentrated sulphuric acid give substituted 1,2,4-triazoles (9,10), 1,3,4-thiadiazoles (11,12) respectively while treatment of (7) with mercuric oxide gave 1,3,4-oxadiazoles (13). Treatment of triazoles (9,10) with 4-hydroxybenzaldehyde gave substituted triazoles (14,15). 1-Substituted thiosemicarbazide (16) was obtained from acid hydrazide (5), cyclized with sodium hydroxide to 5-Substituted-1,2,4-triazole-3-thiol (17). The structures of the synthesized compounds were confirmed by physical and spectral means.

This study involved synthesize (1,3) oxazepine. The step 1 includes the preparation of compound (1), (5-Bromo-2-mercapto-6-(4-methoxyphenyl) pyrimidin-4(3H)-one), by the condensation of anisaldehyde and ethylbromoacetat and thiourea in EtOH. In the step2, chalcones (2-6) have been produced. The reaction of compound (1) with chalcones (2-6) that gives azo Michael adduct (7-11) is made in the third step. Schiff's bases (12-16) were prepared by the reaction ketones (7-11) with 2,4dinitroaniline. Finally preparation of new benzo [1,3] oxazepine compounds (17-21) are prepared by the reaction of phthalic anhydride with Schiff's bases. The synthesized compounds are identified by physical (melting points, colour change) and spectral methods such as (IR, proton-nmr).

The present work involved the synthesis of compound (1) (1-amino-4-methyl-6-phenyl pyrimidine- 2-(1H)-thione). This compound reacts with different aromatic aldehyde using glacial acetic acid as catalytic on absolute ethanol to give a new series of Schiff's bases (2-7). New thiazolidine-4-one were prepared from reactions of Schiff's bases (2,3,4,7) with thioglycolic acid in absolute ethanol giving compounds (8-11). Finally the preparation of new tetrazole derivatives (12-15) by reaction of Schiff's bases (2,3,4,7) with sodium azide in THF. The structure of the synthesized compounds are confirmed by I.R., 1H-NMR and 13C-NMR spectra and some physical  data.