Synthesis of Diarylheptanoid Scaffolds Inspired by Calyxins I and J

Abstract

γ,δ-Unsaturated alcohols are prepared efficiently in two steps from o-hydroxycinnamaldehyde. The TMSOTf-mediated reaction of the γ,δ-unsaturated alcohols with aldehydes creates two oxygen heterocycles and three new stereocenters in a single pot. The approach is versatile, and by varying the boronic acid, Grignard reagent, and aldehyde, different substituents may be introduced, while use of a chiral base in the conjugate addition gives enantioenriched products.

Characterization of diarylheptanoids: An emerging class of bioactive natural products

“…Determination of platyphylloside contents helped the identification of the diverse species and verification of interspecific hybrids [161]. The contents of oregonin in A. glutinosa extracts have been determined using isocratic [140,162] and also gradient [59] C18 HPLC methods. Kinetic analyses on aqueous stability of hirsutenone were carried out by a reversed-phase HPLC method [163].…”

Six-Membered Ring Systems

“…Enynes bearing an aryl halide and a tertiary alcohol capping the alkyne undergo intramolecular formal anti-carbopalladation/Heck reactions to achieve benzodihydrochroman-type compounds (15CEJ12303). Replacing tertiary alcohol by a t-butyl group, lower temperature and reaction time is required for full conversion of substrates (Scheme 29) (15CEJ12303).γ,δ-Unsaturated alcohols, derived from 1,4-addition of phenylboronic acid to 2-hydroxycinnamaldehyde followed by reduction, undergo TMSOTfpromoted reaction with aldehydes to provide a series of pyranochromans (15OL3884). Tandem Prins bicyclization of (E)-3-[2-(4-methoxybenzyloxy)phenyl]-5-phenylpent-4-en-1-ol with aliphatic/aromatic aldehydes carried out in the presence of TMSOTf provides a mixture of trans-fused tetrahydropyran[3,4-c]chromans, one bearing the 4-methoxybenzyl substituent and the other unsubstituted in the aromatic ring.…”

A Chitosan‐CatalyzedDomino Aldol‐Hetero‐Diels‐Alder Synthesis of Cyclic Heptanoid‐Annulated Pyran Scaffolds

“…Willis and co‐workers described a single‐pot method to develop pyran scaffolds, using trimethylsilyl trifluoro methanesulfonate [11] Ngangbam R. Devi and co‐workers reported hexahydropyrano[4,3‐b]pyrans using oxonium‐ene, β‐allenols, aldehydes, and trimethylsilyl trifluoro methanesulfonate [12] . Giventhe interesting bioprofiles of pyran‐heterocycles which contain the cyclic heptanoid core, the synthesis of new candidates of this class would be a significant part of the research in chemical synthesis.…”