Effect of 1, 3-diallylurea and related compounds on growth of transplanted animal tumors.

of urea was investigated in a spectrum of 1 rat and 8 mouse tumors. Repeated i.p. injections of 1,3-diallylurea significantly retarded Carcinoma C1025 and Ridgway osteogenic sarcoma and produced borderline, antitumor effects in 2 other mouse tumors. 1,1-Diallylurea inhibited 2 tumors, but monoallylurea and 1,3-diallylthiourea were inactive. 1,3-Diallylurea against susceptible tumors was characterized by activity over a wide range of nontoxic doses and was independent of the route of administration. Incubation of fragments of susceptible tumors in solutions of 1,3-diallylurea diminished their ability to grow fol lowing s.c. implantation. Comparison of the 13 substituted ureas revealed that antitumor activity was limited to those compounds having a molecu lar structure with 2 ally! groups.