Investigation of heterocycles containing nitrogen or sulfur. 48. Derivatives of 1-morpholinooxalyl-1,2-dihydrothiazolo-[5,4-b]pyridine,their structure,and reactions

The structures of the products of reactions of 1-N-morpholinooxahi-1,2-dihydrothiazolo-5,4-b]pyridine have been studied by IR, NMR, UV, and mass spectroscopy. Geometric (cis-anti) and rotational (about the CO-N amide bond) isomers of 1-N-morpholinooxalyl-2-propionyi-5-chloro-1,2-dihydrothiazolo-5,4-b]pyridine oxime have been observed and studied. Treatment of 1-N-morpholinooxalyl-2-propionyl-5-chloro-1,2-dihydrothiazolo5,4-b]pyridine with ethanolic alkali gave 2-propionyl-5-chlorothiazolo-5,4-b]pyridine, while treatment with concentrated H₂SO₄ gave 1,2-dioxo-ethylidene-7-chloroxazolidino3,2-f]pyrido2,3-b]1,4-thiazine.For Communication 47 see 1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1133–1138, August, 1993.