Preparation of Alkyl-Substituted Indoles in the Benzene Portion. Part 13. Enantiospecific Synthesis of Mitosene Analogues Related to FR 900482 and FR 66979.

Recent developments in indole ring synthesis—methodology and applications

“…ring in hapalindole O 475 and in mitosene analogs related to FR 900482 and FR 66979. 476 The method is particularly effective for the preparation of 4-hydroxyindoles (Scheme 117). 476 The Natsume protocol has been used to synthesize (S)-(Ϫ)pindolol and chuangxinmycin, 477 and Katritzky et al have developed an alternative route to the Natsume cyclization substrates using the lithiation of 2-benzotriazolylmethylpyrroles followed by reaction with α,β-unsaturated aldehydes and ketones.…”

“…476 The method is particularly effective for the preparation of 4-hydroxyindoles (Scheme 117). 476 The Natsume protocol has been used to synthesize (S)-(Ϫ)pindolol and chuangxinmycin, 477 and Katritzky et al have developed an alternative route to the Natsume cyclization substrates using the lithiation of 2-benzotriazolylmethylpyrroles followed by reaction with α,β-unsaturated aldehydes and ketones. [478][479][480] Recently, Natsume and co-workers have synthesized (ϩ)-duocarmycin SA using his indole ring synthesis.…”

Garner's aldehyde

“…46 The addition of indole derivatives to Garner's aldehyde has been used to obtain chiral 2-alkyl-substituted indoles. 47, 48 A practical and stereoselective synthesis of inhibitors of the sphingolipid biosynthesis pathway, namely -threoand erythro-1-phenyl-2-palmitoylamino-3-morpholinopropan-1-ol (PPMP), has been reported by M. Nakagawa et al The erythroprecursor has been obtained by anti-selective addition of PhLi to 1 or 8 respectively (50% yield, anti : syn 3.9 : 1), while oxidation of an anti-syn mixture derived from PhMgBr addition Scheme 6 Addition of metal alkynyl, -vinyl,-alkyl and allyl reagents to 1.…”

Electrophilic Cyclization of Pyrrole

“…In a tour de force over the next ten years, Natsume, Muratake, and colleagues applied their pyrrole-to-indole methodology to the syntheses of the trikentrins [10][11][12][13], pendolmycin [14], (±)-and (S)-pindolol [15], the herbindoles [13,16], hapalindole O [17], mitosene analogues [18], and the duocarmycins [19,20]. Several related companion papers described model studies on these natural products [21][22][23].…”