Alkylation of isatin with 2-chloro-5-(chloromethyl)pyridine yielded a series of novel 1-(pyridin-3-yl)methylindolin-2,3-diones, which were used to obtain water-soluble quaternary ammonium isatin-3-acylhydrazones. The derivatives of 5-fluoroisatin and ammonium salts of a 6-bromoisatin derivative demonstrated the highest in vitro antiaggregation activity, reducing the peak amplitude of platelet aggregation by an average of 14–18%— a result comparable to that of acetylsalicylic acid. At the same time, unlike acetylsalicylic acid, the most active of the synthesized compounds were more effective in prolonging the lag period than (4.6–10.3%). The 6-bromoisatin derivatives exhibited higher antiaggregation activity than their 5-fluoro-substituted analogs.
Bogdanov et al. (Thu,) studied this question.