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A novel synthesis of 4-azoloyl-2-aminoquinolines via the reaction of the 3-cyanomethylene derivatives of isatin with the 2-pyrazolin-5-one derivatives and 2-ethoxycarbonylmethyl-2-thiazolin-4-one is reported.

The reaction of diosgenin (1) with hydrogen peroxide/formic acid was investigated. As a result of this work, 5 α (25 R)-spirostane-3 β,5,6 β-triol (2) was prepared in 79% yield and 5 α-pregnane-3 β,5,6 β,16 β,20 α-pentol (3) in 80% yield. The pentol (3) was oxidised to 5 α-pregnane-3 β,5,10 β,20 α-tetrol-6-one (5) without forming its 16 β,20 α-isopropylidenedioxy derivative (4). Reaction of product 5 with CH3Mgl to give 6-methylpregnane derivative was unsuccessful. Therefore, product 7 was oxidatively degraded by H2O2/HCOOH to the 10-keto pregnane derivative (13) and its structure was proved through its transformation to 6 β-methylpregn-4-ene-6 α,20 α-diol-3,16-dione (15).

The structure of the products of reaction of 2-oxo-3-dicyanomethylidene-2,3-dihydroindole (1a) and 2-oxo-3-cyanoethoxycarbonylmethylidene-2,3-dihydroindole (1b) with the pyrazolin-5-one derivatives 2a,b could be established via 13C nmr and high resolution 1H nmr to be the spiropyranylindolone derivatives 5a-d.

A novel synthesis of 4-azoloyl-2-aminoquinolines via the reaction of the 3-cyanomethylene derivatives of isatin with the 2-pyrazolin-5-one derivatives and 2-ethoxycarbonylmethyl-2-thiazolin-4-one is reported.

The structure of the products of reaction of 2-oxo-3-dicyanomethylidene-2,3-dihydroindole (1a) and 2-oxo-3-cyanoethoxycarbonylmethylidene-2,3-dihydroindole (1b) with the pyrazolin-5-one derivatives 2a,b could be established via 13C nmr and high resolution 1H nmr to be the spiropyranylindolone derivatives 5a-d.

The N-arylmaleimides (I) and cyanothioacetamide (II) are combined to yield the pyrrolo(3,2-b)pyrrole derivatives (III).