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Total syntheses of naturally occurring antiviral indolosesquiterpene alkaloids, xiamycins C-F via Csp³-H functionalization.

ABSTRACT: Concise total syntheses of naturally occurring antiviral indolosesquiterpene alkaloids, xiamycin C (2a), D (2b), E (2c) and F (2d), have been achieved via a late-stage oxidative δ-Csp³-H functionalization of an advanced pentacyclic enone intermediate 8. This strategy takes advantage of ipso-nitration of naturally occurring abietane diterpenoids to synthesize o-bromo nitroarene derivative 11. A Suzuki-Miyaura coupling of 11 with phenylboronic acid followed by Cadogan's ring closure provided a modular approach to a carbazole ring required for a functionalized pentacyclic core of indolosesquiterpene alkaloids.

SUBMITTER: Munda M

PROVIDER: S-EPMC9555729 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Total syntheses of naturally occurring antiviral indolosesquiterpene alkaloids, xiamycins C-F via Csp3-H functionalization.

Munda Mintu M Nandi Rhituparna R Gavit Vipin R VR Kundu Sourav S Niyogi Sovan S Bisai Alakesh A

Chemical science 20220921 39

Concise total syntheses of naturally occurring antiviral indolosesquiterpene alkaloids, xiamycin C (2a), D (2b), E (2c) and F (2d), have been achieved via a late-stage oxidative δ-Csp3-H functionalization of an advanced pentacyclic enone intermediate 8. This strategy takes advantage of ipso-nitration of naturally occurring abietane diterpenoids to synthesize o-bromo nitroarene derivative 11. A Suzuki-Miyaura coupling of 11 with phenylboronic acid followed by Cadog ...[more]

PMID: 36320384

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