Antiparasitic 5-pyrazinyl 1,2-dithiole 3-(thio)one derivs. - prepd. e.g. by reacting alkyl 3-pyrazinyl 3-oxo propionates with phosphorous pentasulphide(BE201276)

摘要

New cpds. are 1,2-dithiole derivs. of formula (I): (where X1,X2 and X3 are H, 1-4 C alkyl or 1-4C alkoxy; at least one of X1,X2 and X3 being H; and Y is S, O or NOH). (I) have low toxicity and display marked chemotherapeutic properties. They are partic. useful as agents against bilharzia, and also have activity against amoebae. Specific cpds. (I) include 5-(2-pyrazinyl)-1,2-dithiole-3-thione. In an example, this cpd. is obtd. in a yield of 15.3g by refluxing 3-(2-pyrazinyl)-3-oxo-propionic acid ethyl ester (97g) with P2S5 (122g) in anhydrous pyridine (1220 ml).