Biosynthesis and function of polyacetylenes and allied natural products

Abstract

Polyacetylenic natural products are a substantial class of often unstable compounds containing a unique carbon-carbon triple bond functionality, that are intriguing for their wide variety of biochemical and ecological functions, economic potential, and surprising mode of biosynthesis. Isotopic tracer experiments between 1960 and 1990 demonstrated that the majority of these compounds are derived from fatty acid and polyketide precursors. During the past decade, research into the metabolism of polyacetylenes has swiftly advanced, driven by the cloning of the first genes responsible for polyacetylene biosynthesis in plants, moss, fungi, and actinomycetes, and the initial characterization of the gene products.The current state of knowledge of the biochemistry and molecular genetics of polyacetylenic secondary metabolic pathways will be presented together with an up-to-date survey of new terrestrial and marine natural products, their known biological activities, and a discussion of their likely metabolic origins.

Anticancer Activities of Polyynes from the Root Bark of Oplopanax horridus and Their Acetylated Derivatives

“…Polyynes, namely polyacetylenes, have been found in many food and dietary plants [1][2][3][4][5]. To date, pharmacological investigations have revealed that polyynes from natural sources show antibacterial, anti-fungal, antiinflammatory, nerotoxic and anticancer activities [6][7][8][9].…”

The convergent evolution of defensive polyacetylenic fatty acid biosynthesis genes in soldier beetles

“…Polyacetylenic fatty acids, containing more than one triple bond in the molecule, are produced and sequestered by a wide variety of organisms in many environments; more than 2,000 of these molecules have been identified in higher plants, liverworts, mosses, fungi, marine sponges and algae 19 . Many polyacetylenics have highly potent biological activities, which are used in defence against pathogens and predators 3,12,15 , and some have been investigated as human anti-cancer and anti-microbial treatments 13,16,18,20 .…”

“…The challenging chemistry and variety of potent biological activities of polyacetylenic fatty acids, which includes activities against cancer cells, infecting microbes and plant alleopathy [12][13][14][15][16][17][18][19][20] , have excited interest among natural-product prospectors and bioactive discovery programmes, and have propelled our interest in new molecular structures and biosynthetic origins. In this report, we describe a three-gene pathway isolated from the Australian soldier beetle C. lugubris, leading to an 18-carbon precursor of DHMA, and the first eukaryote biosynthesis of conjugated polyacetylenic compounds.…”

DFT studies and crystal structure of synthesized 1,3-bis(2-thiophenylmethyl)-4,5-dihydroimidazolidinium hexafluorophosphate salt

“…The catalytic activity can be changed with the substituents on the N atom of the salts such as imidazolium, imidazolidinium or bisbenzimidazolium [5,8]. Carbon-carbon cross-coupling reactions, which play an important role in the synthesis of natural products, drug design and industrially important starting materials, have been an area of interest for organic chemists for a long time [9][10][11].…”