الفهرس 
Aim of the workOnly 14 pages are availabe for public view
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Abstract
1. First part:-
A mixture of dimethyl but-2-ynedicarboxylate and 1,6-disubstituted 2,5-dithiobiureas were refluxed in ethanol, afforded dimethyl (hydrazine-1,2-diylidine)bis-(3-aryl/alkyl-4-oxothiazolidine-5,2-diylidene)diacetate, methyl-(2-methoxy-2-oxo-ethylidene-4-oxo-thiazolidin-2-yl¬idene)¬hy¬draz¬o¬-no-4-oxo¬¬thia-zolidinylidene)acetate deri¬vatives in (69-77%) and 2,5-disubstituted 2,5-diamino¬[1,3,4]thiadiazoles in (14-19%).
2. Second part:-
To a stirred solution of CNIND in tetrahydrofuran (THF), a solution of symmetrical and unsymmetrical 1,6-disubstituted-2,5-dithiobiureas were added. The reaction mixtures were stirred for 96 hours at room temperature in a molar ratio of 3:1 with admission of air to give oxa-aza[3.3.3]propellane (11-16%), bis-oxathiaaza[3.3.3]-propellanes (58-62%), in addition to 2,5-disubstituted 2,5-diamino¬[1,3,4]-thiadiazoles (14-19%).
3. Third part:-
The coupling reaction between (E)-hex-2-en-ylidene-N-substituted hydrazinecarbothioamides and the electron poor 2,3-dichloro-1,4-naphthoquinone (DCHNQ) affords substituted amino-5-pentenylnaphtho[2,3-f]-1,3,4-thiadiazepine-6,11-diones and 2-(substituted amino)naphtho[2,3-d]thiazole-4,9-diones. These conversions can be rationalized by proposing a nucleophilic addition to C2 and C3 of dichloro-1,4-naphthoquinone.