Pyrazolidines as pharmaceuticals or - intermediates

摘要

Pyrazolidines are prepared by condensing a mixture of hydrazine deriv. R1NHNH2, (where R1 = phenyl, methyl- or dimethyl-phenyl, or acyl); and olefin R3 CH = CR4R5, (where R3 and R4 = H or CH3; and R5 = phenyl, vinyl or CH3, but R5 = CH3 when R4 = H). In particular, phenylhydrazine, paraformaldehyde and styrene are condensed in aqueous acetic acid (70-100%). The products have valuable pharmaceutical applications or may be hydrogenated to obtain 1,3-diamines.