Abstract
Two samples obtained by distillation of the chlorinated product of 4-n-octylresorcinol (O. R.) under the higher temperature with lower reduced pressure than is ordinarily used were both proved to be superior in the anthelmintic efficacy against ascaris in man, than pure 4-n-ecty1-6-chlororesorcinol (O.C.R.). These samples were (1) lower in melting point, (2) more distinctly colored by the diazo-reaction, (3) stronger in interfacial activity of the solution, (4) more efficacious in ascaricidal action in vitro, (5) slightly more toxic and irritant and (6) contained less chlorine than pure crystal of O.C.R.. If we assume that all this chlorine depends upon O.C.R., then these samples must contain 23.8 and 27% impurities which have no chlorine respectively. Mixtures of O.C.R. and O.R. have excellent anthelmintic efficacy, when percentage of the latter lies between 20 and 30 (refer to preceding report), besides having biological and physico-chemical properties which are almost similar, in both quality and quantity, to the samples above mentioned. Moreover, a fairly large amount of O.R. together with traces of resorcinol and 6-chlororesorcinol besides O.C.R. was identified in these samples by a paper chromatographic method, and it was proved that these impurities could be produced by thermal decomposition of O.C.R.. Occasional differences in efficacy of O.C.R. preparations in manufactural lots may be explained in most part to be caused by the concomitant of O.R..
