Potent Anti-Ovarian Cancer with Inhibitor Activities on Both Topoisomerase II and (V600E)BRAF of Synthesized Substituted Estrone Candidates

A series of 16-(α-alkoxyalkane)-17-hydrazino-estra-1(10),2,4-trien[17,16-c]-3-ol (3a–l) and estra-1(10),2,4-trien-[17,16-c]pyrazoline-3-ol derivatives (4a–d) were synthesized from corresponding arylidines 2a,b which was prepared from estrone 1 as starting material. Condensation of 1 with aldehydes gave the corresponding arylidine derivatives 2a,b which were treated with hydrazine derivatives in alcohols to give the corresponding derivatives 3a–l, respectively. Additionally, treatment of 2a,b with methyl- or phenylhydrazine in ethanolic potassium hydroxide afforded the corresponding N-substituted pyrazoline derivatives 4a–d, respectively. All these derivatives showed potent anti-ovarian cancer both in vitro and in vivo. The mechanism of anti-ovarian cancer was suggested to process via topoisomerase II and (V600E)BRAF inhibition.