Synthesis of Ring Size seco‐Analogs of the Antitumor Antibiotic CC‐1065 by Two Consecutive Transition Metal‐Initiated Transformations

Abstract

Novel seco‐analogs of CC‐1065 1 were synthesized from comercially available nitroaniline by reduction, bromination, bisulfonation and bisallylation followed by reaction with tert‐butyllithium, zirconocene and iodine. The obtained quinoline 6 was then transformed into 17 and 18, which, upon treatment with Pd0, led to 21 and 22, respectively. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

Total Synthesis of the Photoprotecting Dipyrrolobenzoquinone (+)-Terreusinone

“…In light of this disappointing result, a two-step dibromination was considered. Thus, the known bromide 7 underwent successful bromination (NBS, H 2 SO 4 ), affording dibromides 3c and 9 , again heavily favoring the undesired regioisomer 9 (93:7) (Scheme ). However, acetylation of bromide 7 gave 8 that, upon exposure to the conditions used previously (NBS, H 2 SO 4 ), underwent bromination with concomitant acetate hydrolysis, giving bromides 3c and 9 , pleasingly favoring regioisomer 3c in a 2:1 ratio (Scheme ).…”