Synthesis, characterization and reactions of 2-deoxo-5-deazaalloxazines.

5-Deazaflavins and their homologues have been known as potential riboflavin antagonists, bioreductives, and compounds with potent antitumor activity. 2-Amino-4-methylquinoline-3-carbonitrile (2) was prepared as unreported starting material for several interesting 2-deoxo-5-deazalloxazine derivatives. Cyclization of 2 using formamide afforded the 2,4-deoxo-5-deazaalloxazine derivative 7, which was subjected to deamination with nitrous acid to give the 2-deoxo-5-deazaalloxazine (8). The compound 8 was also obtained via 13 by treating the latter with refluxing formic acid or formamide and used as a precursor for synthesis of several 2-deoxo-5-deazaalloxazines 18, 19, 20, 21 and 22. The pharmacological and biological properties of these compounds are still under investigation.

Toxic effect of ethanolic extract of Nerium oleander (Apocynaceae) leaves against different developmental stages of Muscina stabulans (Diptera-Muscidae).

Nerium oleander (Apocynaceae) is evergreen shrubs widely used for ornamental purpose in mediterranean region. The present investigation, revealed for the first time the insecticidal effect of ethanolic extract from leaves of this plant against 2nd instar larvae of the medically important false stable fly Muscina stabulans (Diptera: Muscidae). LC50 of the extract was 113.66 ppm. This dose delayed larval and pupal duration suppressed oviposition and decreased adult longevity of the survivors. Morphogenic abnormalities were recorded and photographed in larval, pupal and adult stages, which were produced from treating 2nd instar larvae with different concentrations of the extract.

Synthesis and biological activity of some new benzimidazolyl-azetidin-2-ones and -thiazolidin-4-ones.

Arylidene-2-aminobenzimidazoles (1) were prepared by condensation of 2-aminobenzimidazole with aromatic aldehydes. Cyclocondensation of mercaptoacetic acid, chloracetylchloride and phthaloyl glycyl chloride on 1 giving the corresponding 4-thiazolidinones (2) and azetidinones (3 and 4) respectively, in good yields. The biological activities of the prepared compounds were screened against several strains of bacteria.

Synthesis of some new heterocyclic 1,3,4-oxadiazoles with antibacterial activity.

2-N-Aryl/heterocyclic carboxamidomethylthio-5-p-chlorophenyl-1,3,4-oxadiazoles have been synthesized by the reaction of 1 and N-aryl/heterocyclic-2-chloracetamides in presence of basic medium. 2 and 3 react with heterocyclic thiols in ethanolic potassium hydroxide to give 3-S-substituted-mercaptomethyl-5-substituted-phenyl-1,3,4-oxadiazol-2-thione 5 and 6 respectively. Tert. amines react with 2 to yield the corresponding amino chlorides in good yield. Some of the prepared compounds were tested as antibacterials against Gram-positive and Gram-negative organism.