77556-69-5Relevant academic research and scientific papers
Syntheses with 1,3-Dithietanes. XIII. Syntheses of Condensed Heterocycles from 5-Thioxo-3-pyrazoline-4-carboxylates
Peseke, K.,Vogel, C.,Blaesche, J.,Kollhof, K.-H.
, p. 639 - 651 (2007/10/02)
3-Amino-2-aroyl-5-thioxo-4-pyrazoline-4-carboxylates 1d-f react with bromoacetaldehydediethylacetale, phenacyl bromides, ethyl bromopyruvate, ethyl α-chloro-acetate or chloroacetylacetone to give ethyl dihydropyrazolothiazolecarboxylates 2, 4, 5 or 7.The derivatives of ethyl tetrahydropyrazolothiazolecarboxylates 8 or 9 are obtained by reaction of 1d-f with ethyl β-anilino-α-chloro-crotonate and oxalylchloride, respectively.The ethyl methylthiopyrazolinecarboxylate 10 d and an excess of hydrazine hydrate afford pyrazolopyrazole 11.Compounds 10 react with phenyl isocyanate to give pyrazolooxazin-6-ones 13.The dithietanes 12 and cinnamohydrazide yield pyrazolopyrazolecarboxylates 15.
