Enantiomerically Pure Allylboronic Esters as Versatile Reagents in the Enantioselective Synthesis of Dihydro-α-pyrone-Containing Natural Products

Abstract

A short and efficient enantio-and diastereoselective synthesis of different representatives from the class of dihydro-α-pyrone natural products, including both enantiomers of goniothalamin, massoia lactone, parasorbic acid, and some derivatives is presented. It is based on the application of enantiopure α-chiral allylboronic esters in allyl additions.

Chemical Constituents from the deep‐sea‐derived Fungus Aureobasidium melanogenum LUO5

“…By comparison of the NMR, MS, and optical rotation data with those reported in the literature, eight known compounds were identified as (3 R ,5 R )‐methyl 3,5‐dihydroxydecanoate ( 7 ), [20,21] massoia lactone ( 8 ), [22] (3 R ,5 R )‐3‐hydroxy‐5‐decanolide ( 9 ), [23] (+)‐2‐oxo‐6‐pentyltetrahydro‐2 H ‐pyran‐4‐yl acetate ( 10 ), [24] 2,3‐dihydroxypropyl (9 Z )‐9‐heptadecenoate ( 11 ), [25] 1‐monolinolein ( 12 ), [26] uridine ( 13 ), [27] and acetyl‐ L ‐tryptophan ( 14 ) [28] …”

“…By comparison of the NMR, MS, and optical rotation data with those reported in the literature, eight known compounds were identified as (3R,5R)-methyl 3,5-dihydroxydecanoate ( 7), [20,21] massoia lactone (8), [22] (3R,5R)-3-hydroxy-5-decanolide (9), [23] (+)-2-oxo-6-pentyltetrahydro-2H-pyran-4-yl acetate (10), [24] 2,3-dihydroxypropyl (9Z)-9-heptadecenoate ( 11), [25] 1monolinolein ( 12), [26] uridine (13), [27] and acetyl-L-tryptophan ( 14). [28] Microglial activation closely related to the pathogenesis of neurodegenerative diseases, such as multiple sclerosis and Alzheimer's and Parkinson's diseases.…”