الفهرس 
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Abstract
The synthesis of -2-(benzo[d]thiazol-2-yl)-3-(4-chlorophenyl)acrylonitrile (2) was carried out according to reported literature by treatment of benzothiazolyl-acetonitrile (1) with 4–chlorobenzaldehyde. Thus, the benzothiazole derivative 2 act as a precursor for the synthesis of novel benzothiazolopyridine derivatives. Synthetic route of benzothiazolopyridine derivatives is shown in Scheme 1. Accordingly, the reaction of 2 with indandione under refluxing in EtOH including catalytic drops of piperidine afforded benzothiazolopyridine derivative 5. The formation of 5 was occurred firstly by Michael addition of the activated methylene of indanedione to the activated double bond in compound 2 to form imine Michael adduct intermediate 3, which converted to enamine intermediate 4 that underwent an intramolecular cyclocondensation to give finally isolable product 5. In a similar manner and methodology, treatment of 2 with thiobarbituric acid furnished 5-(4-chlorophenyl)-4-oxo-2-thioxo-1,3,4,5-tetrahydro-2H-benzo[4’,5’]thiazolo[3’,2’:1,6]pyrido[2,3-d]pyrimidine-6-carbonitrile (6) (Scheme 1). The benzothiazolopyridine compound 7 (Scheme 1) was prepared as reported in literature.