Craig Stacy Takeuchi

New taxanes as highly efficient reversal agents for multi-drug resistance in cancer cells

New non-cytotoxic taxanes synthesized from 10-deacetylbaccatin III and special hydrophobic acylating agents show remarkable MDR reversal activity (< or = 99.8%) against drug-resistant human breast cancer cells when co-administered with paclitaxel or doxorubicin. This activity is ascribed to the highly efficient blocking of P-glycoprotein efflux by these new taxanes.

Discovery of a novel class of highly potent, selective, ATP-competitive, and orally bioavailable inhibitors of the mammalian target of rapamycin (mTOR).

A series of novel, highly potent, selective, and ATP-competitive mammalian target of rapamycin (mTOR) inhibitors based on a benzoxazepine scaffold have been identified. Lead optimization resulted in the discovery of inhibitors with low nanomolar activity and greater than 1000-fold selectivity over the closely related PI3K kinases. Compound 28 (XL388) inhibited cellular phosphorylation of mTOR complex 1 (p-p70S6K, pS6, and p-4E-BP1) and mTOR complex 2 (pAKT (S473)) substrates. Furthermore, this compound displayed good pharmacokinetics and oral exposure in multiple species with moderate bioavailability. Oral administration of compound 28 to athymic nude mice implanted with human tumor xenografts afforded significant and dose-dependent antitumor activity.

Sar and in Vivo Evaluation of 4-Aryl-2-Aminoalkylpyrimidines as Potent and Selective Janus Kinase 2 (Jak2) Inhibitors

We report the discovery of a series of 4-aryl-2-aminoalkylpyrimidine derivatives as potent and selective JAK2 inhibitors. High throughput screening of our in-house compound library led to the identification of hit 1, from which optimization resulted in the discovery of highly potent and selective JAK2 inhibitors. Advanced lead 10d demonstrated a significant dose-dependent pharmacodynamic and antitumor effect in a mouse xenograft model. Based upon the desirable profile of 10d (XL019) it was advanced into clinical trials.