Anti-implantation agents: Part I. 1-Arylthiosemicarbazides

Abstract

Several 1-arylthiosemicarbazides, 2-arylhydrazinothiazolines and 2-arylhydrazinodihydrothiazines have been examined for their antiimplantation activity in rats. Among the active compounds, 4-methyl-1-(3,5-bistrifluorornethylphenyl)thioserni-carbazide (3, C 2696-Go) and the corresponding 4,4-dimethyl (47), ethyl (4), n-butyl (5) and allyl (6) derivatives completely inhibit implantation at doses of 10, 3, 20, 20 and 30mg/kg respectively. The 3,4-dichlorophenyl analogue (32) is effective at a dose of 30mg/kg. 2-(3,5-Bistrifluoromethylphenyl)hydrazinothiazoline (51) and the corresponding dlhydrothiazine (63) show a weaker activity. The biological profile of C 2696-Go has been investigated in detail. It appears to prevent implantation by its antiuterotropic activity and ability to inhibit desiduoma formation.