Evolution of Total Syntheses of β‐Hydroxy‐γ‐Lactones: Cardiobutanolide and Hagen's Gland Lactones

Abstract

The b-hydroxy-g-lactones, cardiobutanolide and Hagen's gland lactones have been interesting targets for total synthesis in many laboratories. There are 10 syntheses reported for cardiobutanolide and 19 syntheses for Hagen's gland lactones. These natural products have the b-hydroxy-g-lactone moiety in common. The evolution of various synthetic strategies to these natural products from chiral pool materials and/or asymmetric catalysis and involving linear sequences, convergent approaches to the de-novo protecting group free syntheses have been abstracted in this review.[a] Prof.

The Potential of β‐Hydroxy‐γ‐vinyl‐γ‐lactone in the Synthesis of Natural Products and Beyond

“…To overcome this, we adopted the Upjohn oxidation to furnish the diastereomeric mixture of 36b and (+)‐cardiobutanolide ( 36a ) in 1:4 ratio, the latter being isolated in 61 % yield. This marks to be the shortest synthesis of (+)‐cardiobutanolide in the literature and achieved without using any protecting groups.…”

“…A final de‐iodination provided the Hagen's gland lactones ( 42a or 43a ), respectively, in just 4 steps from 2 via 1 in overall yields of 37.4 and 25.6 %. The strategy is protecting‐group‐free and marks the shortest synthesis of these natural products known in the literature . Considering the toxicity of stannane and the use of carcinogenic solvent benzene, we refined the procedure for de‐iodination using catalytic hydrogenation .…”

Advances in Total Synthesis of Some 2,3,5‐Trisubstituted Tetrahydrofuran Natural Products

“…All the synthetic attempts on these molecules till 2016 have been reviewed by us. [13] Since then, there is one report on their synthesis recently. Chowhan and co-workers [100] in 2019 synthesized Hagen's Gland lactones using vinylogous Mukaiyama type reaction and intramolecular oxa-Michael addition as key steps (Scheme 38).…”

“…[12] Various syntheses of these lactones 5 up to the year 2016 have been reviewed. [13] Considering the significance of these molecules, presence of many related THF-compounds in nature and scattered literature on their synthesis, a compilation on the arduous synthetic efforts is desired. Many of the synthetic strategies are extended toward the bigger class of compounds under the family of acetogenins.…”

Recent Advances in Total Synthesis of Bioactive Furo[3,2‐b]furanone Natural Products

“…through enantioselective total synthesis . Less than a handful of synthesis of 88 and 89 were reported prior to 2000 …”