Synthesis of phenolic components of Grains of Paradise

Synthesis and Anti-Proliferative Evaluation of Arctigenin Analogues with C-9' Derivatisation

Dibenzylbutyrolactone lignans (DBLs) are a class of natural products with a wide variety of biological activities. Due to their potential for the development of human therapeutic agents, DBLs have been subjected to various SAR studies in order to optimise activity. Previous reports have mainly considered changes on the aromatic rings and at the benzylic carbons of the compounds, whilst the effects of substituents in the lactone, at the C-9' position, have been relatively unexplored. This position has an unexploited potential for the development of novel dibenzyl butyrolactone derivatives, with previous preliminary findings revealing C-9'-hydroxymethyl analogues inducing programmed cell cycle death. Using the core structure of the bioactive natural product arctigenin, C-9' derivatives were synthesised using various synthetic pathways and with prepared derivatives providing more potent anti-proliferative activity than the C-9'-hydroxymethyl lead compound.

Isolation, Structure Characterization, Total Synthesis and Biological Evaluation of Cinnamic Acid Derivatives from Tinospora sagittata

Thirteen cinnamic acid derivatives (1-13), including six formerly unreported hybrids incorporating different short-chain fatty acid esters (1-6), have been obtained and structurally elucidated from an ethnological herb Tinospora sagittata. The structures of them have been established by spectroscopic data analyses and NMR comparison with known analogs, while those of 1, 2, 4 and 6 have been further supported by total synthesis, and it is the first report of this type of metabolites from the title species. All the isolates have been assessed in an array of bioassays encompassing cytotoxic, antibacterial, anti-inflammatory, antioxidant, as well as α-glucosidase and HDAC1 inhibitory models. Compound 7 showed significant inhibitory activity against α-glucosidase, and half of the isolates also displayed moderate antiradical effect.

Stereoselective Biocatalyzed Reductions of Ginger Active Components Recovered from Industrial Wastes

Ginger is among the most widespread and widely consumed traditional medicinal plants around the world. Its beneficial effects, which comprise e. g. anticancer and anti-inflammatory activities as well as gastrointestinal regulatory effects, are generally attributed to a family of non-volatile compounds characterized by an arylalkyl long-chained alcohol, diol, or ketone moiety. In this work, ginger active components have been successfully recovered from industrial waste biomass of fermented ginger. Moreover, their recovery has been combined with the first systematic study of the stereoselective reduction of gingerol-like compounds by isolated alcohol dehydrogenases (ADHs), obtaining the enantioenriched sec-alcohol derivatives via a sustainable biocatalytic path in up to >99 % conversions and >99 % enantiomeric/diastereomeric excesses.

First enantioselective synthesis of gingesulfonic acids and unequivocal determination of their absolute stereochemistry

Herein we report the first organocatalysed enantioselective synthesis of gingesulfonic acids and shogasulfonic acids via a mild and convenient aminothiourea-catalysed conjugate addition of bisulfite to the olefin moiety of α,β-unsaturated carbonyls-a technology previously reported by us. A series of optically active naturally occurring sulfonic acids are prepared in their natural and unnatural configurations, and their absolute configurations are unequivocally confirmed by single crystal X-ray diffractometry.