Bifidenone: Structure–Activity Relationship and Advanced Preclinical Candidate

Bifidenone is a novel natural tubulin polymerization inhibitor that exhibits antiproliferative activity against a range of human cancer cell lines, making it an attractive candidate for development. A synthetic route was previously developed to alleviate supply constraints arising from its isolation in microgram quantities from a Gabonese tree. Using that previously published route, we present here 42 analogues that were synthesized to examine the structure–activity relationship of bifidenone derivatives. In addition to in vitro cytotoxicity data, data from murine xenograft and pharmacokinetic studies were used to evaluate the analogues. Compounds <b>45b</b> and <b>46b</b> were found to demonstrate promising efficacy in murine xenograft experiments, and <b>46b</b> had significantly more potent in vitro antiproliferative activity against taxane-resistant cell lines compared to that of paclitaxel

Design and Synthesis of 4‑Heteroaryl 1,2,3,4-Tetrahydroisoquinolines as Triple Reuptake Inhibitors

A series of 4-bicyclic heteroaryl 1,2,3,4-tetrahydroisoquinoline inhibitors of the serotonin transporter (SERT), norepinephrine transporter (NET), and dopamine transporter (DAT) was discovered. The synthesis and structure–activity relationship (SAR) of these triple reuptake inhibitors (TRIs) will be discussed. Compound <b>10i</b> (AMR-2), a very potent inhibitor of SERT, NET, and DAT, showed efficacy in the rat forced-swim and mouse tail suspension models with minimum effective doses of 0.3 and 1 mg/kg (<i>po</i>), respectively. At efficacious doses in these assays, <b>10i</b> exhibited substantial occupancy levels at the three transporters in both rat and mouse brain. The study of the metabolism of <b>10i</b> revealed the formation of a significant active metabolite, compound <b>13</b>