101968-75-6Relevant academic research and scientific papers
Stereodivergent Total Synthesis of Hapalindoles, Fischerindoles, Hapalonamide H, and Ambiguine H Alkaloids by Developing a Biomimetic, Redox-Neutral, Cascade Prins-Type Cyclization
Sahu, Samrat,Das, Beauty,Maji, Modhu Sudan
, p. 6485 - 6489 (2018/10/24)
A stereoselective, redox-neutral, Br?nsted acid-catalyzed cascade Prins-type cyclization between indole and aldehyde is described to access several structurally diverse indole terpenoid scaffolds in a single step. Applying this concept, stereodivergent to
Discovery of a Calcium-Dependent Enzymatic Cascade for the Selective Assembly of Hapalindole-Type Alkaloids: On the Biosynthetic Origin of Hapalindole U
Zhu, Qin,Liu, Xinyu
supporting information, p. 9062 - 9066 (2017/07/25)
Hapalindole U (4) is a validated biosynthetic precursor to ambiguine alkaloids (Angew. Chem. Int. Ed. 2016, 55, 5780), of which biogenetic origin remains unknown. The recent discovery of AmbU4 (or FamC1) protein encoded in the ambiguine biosynthetic pathway (J. Am. Chem. Soc. 2015, 137, 15366), an isomerocyclase that can rearrange and cyclize geranylated indolenine (2) to a previously unknown 12-epi-hapalindole U (3), raised the question whether 3 is a direct precursor to 4 or an artifact arising from the limited in vitro experiments. Here we report a systematic approach that led to the discovery of an unprecedented calcium-dependent AmbU1-AmbU4 enzymatic complex for the selective formation of 4. This discovery refuted the intermediacy of 3 and bridged the missing links in the early-stage biosynthesis of ambiguines. This work further established the isomerocyclases involved in the biogenesis of hapalindole-type alkaloids as a new family of calcium-dependent enzymes, where the metal ions are shown critical for their enzymatic activities and selectivities.
Total synthesis of hapalindole-type natural products
Lu, Zhaohong,Yang, Ming,Chen, Pengxi,Xiong, Xiaochun,Li, Ang
supporting information, p. 13840 - 13844 (2015/03/13)
A unified and bioinspired oxidative cyclization strategy was used in the first total syntheses of naturally occurring 12-epi-hapalindole Q isonitrile, hapalonamide H, deschloro 12-epi-fischerindole I nitrile, and deschloro 12-epi-fischerindole W nitrile, as well as the structural revision of the latter. Hapalindoles H and Q were also synthesized.
Total synthesis of hapalindoles J and U
Rafferty, Ryan J.,Williams, Robert M.
, p. 519 - 524 (2012/03/26)
The total synthesis of d,l-hapalindoles J and U has been accomplished. Hapalindole J was prepared in 11% overall yield over 11 synthetic steps and hapalindole U was prepared in 25% overall yield over 13 synthetic steps from commercially available materials. The route employs a novel silyl ether-based strategy for accessing the 6:5:6:6 ring system of the hapalindoles rapidly and in good yields.
Synthetic studies of marine alkaloids hapalindoles. Part 3. Total synthesis of (±)-hapalindoles H and U
Muratake, Hideaki,Kumagami, Harumi,Natsume, Mitsutaka
, p. 6351 - 6360 (2007/10/02)
A total, synthesis of marine indole alkaloids (±) -hapalindoles H (1) and U (2) was achieved from the previously described compound 7 by way of 13, 21, and 26 for U (2), and 33 and 32 for H (1).
