Evaluation of certain ureas and nitrosoureas of 2,3-dihydro-1,4-benzothiazines against Sarcoma-180 solid tumors in vivo.

Different derivatives of nitrosoureas were synthesized by a long sequence of reactions and were evaluated for their anticancer activities against female Swiss albino mice, 6-8 weeks old, weighing 18-24 g and bearing Sarcoma-180 (S-180) ascitic tumor. Experimental protocols include injecting a total of 2 x 10(5) S-180 viable ascitic cells s.c. on day 0 in the left flank of mice to obtain solid tumors, followed by the treatment of urea/nitrosourea derivatives on days 1, 5 and 9 at different dose levels. Of the 32 compounds tested, eight were found highly active against solid tumors with significant growth delay and tumor weight inhibition ratio. 5-Fluorouracil was injected s.c. as referent compound to positive control animals.