Nicandrenone, an insecticidal plant steroid derivative with ring D aromatic

Abstract

Though in enzymatic reactions nicotinamide-adenine dinucleotide (NADH) serves as a reducing agent for aldehydes, via direct hydrogen transfer, rather extensive search has led to no aldehyde substrate reducible by 1.4-dihydropyridine in simple model systems operating in aqueous solution at ambient temperature.1 For horse liver alcohol dehydrogenase the Zn11 species present at each of the two NADH-containing active sites has been suggested to facilitate aldehyde reduction by polarization of the carbonyl group through direct interaction with the carbonyl oxygen.2 Though Creighton and Sigman3 have quite recently described a Zn11dependent reduction of 1,10-phenanthroline-2-carboxaldehyde by A-propyl-1,4-dihydronicotinamide (NPrNH), this system, being reported only in acetonitrile, is apparently restricted to aprotic solvents. Apparently searches for aldehyde substrates have never been directed to pyridoxal phosphate and analogs. This is rather surprising considering the fact that, as cofactors, NADH and pyridoxal phosphate cohabit in the same cell milieu. We report herein that pyridoxal phosphate (PLP), pyridoxal (PL), and 3-hydroxypyridine-4-aldehyde (PCHO) serve as suitable aldehyde substrates for reduction by the 1,4-dihydropyridines, NPrNH, and 2,6-dimethyl-3,5-dicarbethoxy-l,4-dihydropyridine (Hantzsch ester). Also, we find the reductions to be facilitated by metal ions in aqueous solution. Kinetic studies were carried out spectrophotometrically under No in Thunberg cuvettes employing two media: (a) neat boiling methanol (NPrNH at 354 nm, Hantzsch ester at 372 nm); and (b) 52.1 wt % (4) D. S. Auld and T. C. Bruice, ibid., 89, 2083Bruice, ibid., 89, (1967.(5) For a review of the work of E. E. Snell, D. E. Metzler, and others, see ref 1, Chapter 8.

Withasteroids, a Growing Group of Naturally Occurring Steroidal Lactones

“…8a,17a (80,84,88,91) Nicandrenolactone ( = Nic-l lactone) (190) 8a (92) Salpichrolide A (191) 10a (159) F. Jaborols (Ring A Aromatic Withanolides and Precursor) laborol (192) 6d (72,75) laborosalactone Q (193) 6c…”

“…The insect repellent and insecticidal properties of nicandrenone (189) and the insect antifeedant property of withanolide E (150) and of a number of related natural and synthetically modified withanolides have been studied (13,84,94,254). Further investigation of this property of withasteroids is expected to yield fruitful results.…”

Withanolides from Leaves of Nicandra physalodes

“…From this species, several withanolides have been reported possessing either the normal or modified skeletons (ring-D aromatic). [6][7][8][9][10][11][12] N. physalodes is considered an ornamental plant possessing insect repellent properties. In fact, its main constituent named as nicandrenone showed antifeedant activity.…”

“…[6][7][8]13 In a continuing effort to isolate active compounds from the Brazilian Solanaceae, the acetone extract from N. physalodes was investigated. As results, five new withanolides (15-oxonicaphysalin B (1), 6β,7α-dihydroxynicandrenone 10 (2), 24α ,25β -dihydroxy-nicandrenone-2 (3 ) and a mixture of the epimers 17-(1α/1β-methylpropanone)-nicandrenone (4a/4b)), in addition to nicandrenone-10 (5), nicandrenone (6), nicandrenone-7 (7), 10 nicandrenone-2 (8), 7 nicaphysalin B (9), 9 and 26R-withahisolide G (10), 12 were isolated. The isolated compounds were evaluated for their antibacterial and antifungal effects.…”

Biotransformation of Physalin H and Leishmanicidal Activity of Its Transformed Products

“…1,2) Previous studies have shown that the steroidal lactones (withanolides and physalins) exhibit a range of biological activities, including anti-tumor, 3) immunomodulatory, 4) antimycobacterial, 5) anti-fungal, anti-inflammatory, 6,7) insect repellant, 8) and immunostimulating properties. 9) Compound 1 has also shown moderate cytotoxic activity against HeLa cells.…”