Efficient Synthesis and Spectroscopic Characterization of Biologically Relevant Pregnane Derivatives, and its Glycoside

Objective:: In present research article, we synthesized novel pregnane derivatives from 16-dehydropregnenolone acetate (1) which has been obtained by the degradation of naturally occurring plant product-diosgenin. The oxime esters, 3β-acetoxy-pregn-5,16-diene, 20-one O-(2-(6-methoxynaphthalene-2yl) propionyl) oxime (5) and 3β-hydroxy-pregn-5, 16-diene, 20-one O-(2-(4-isobutyl phenyl) propionyl) oxime (6) have been synthesized by reaction of 3β-acetoxy-5,16-pregna-dien-20-oxime (3) with NSAIDs Ibuprofen and naproxen respectively. Methods:: The epoxide derivative 3β-hydroxy-16α, 17α-epoxypregn-5-ene-20-one (4) was opened by BF3.Et2O and yielding product 3,16-di-hydroxy pregn-5-ene-20-one (7) and 3,16,17-tri-hydroxy pregn-5-ene-20-one (8), both the synthesized compounds undergoes esterification with Ibuprofen afforded 3,16-di-(2-(4-isobutyl phenyl) propionoxy) pregn-5-ene-20-one (9) and 3,16-di-(2-(4-isobutyl phenyl) propionoxy) 17-hydroxy pregn-5-ene-20-one (10) respectively. Results and Conclusion:: A one novel pregnane glycoside 3β-[2′,3′,4′,6′-tetra-O-acetyl-β-D-glucopyranosyl]-Oxy-20β-hy-droxy-16α-methoxy-pregn-5-ene (15) has also been synthesized from 3β, 20β-dihydroxy-16α-methoxy-pregn-5-ene (12). After the synthesis all the compounds have been characterized by modern spectroscopic techniques.

An Efficient Procedure for the Synthesis of 21-Acetoxypregna-1,4,9(11),16- tetraene-3,20-dione

Background: Halogenated corticosteroids are widely used in medicine, and the global need of these steroidal APIs is estimated to be 40 – 70 tons, annually. Vietnam currently imports the pharmaceutical compounds up to 90%, in particular 100% of steroidal drugs. Currently, industrial production is based on the chemical syntheses of corticosteroids from either 16- dehydropregnenolone acetate (obtained from diosgenin) or androstenedione (obtained from phytosterol). The development of shorter synthetic schemes and more economically feasible technologies is of great significance. Introduction of 1(2)-double bond at the final stages of the corticosteroids synthesis results inpoor yield. 21-Acetoxypregna-1,4,9(11),16-tetraene-3,20-dione (tetraene acetate) is a key intermediate in the synthesis of highly active halogenated corticosteroids such as dexamethasone and other halogenated corticosteroids. 21-acetoxypregna-1,4,9(11),16- tetraene-3,20-dione is a key intermediate in the synthesis of dexamethasone from the readily available and cheap 9α-hydroxyandrost-4-ene-3,17-dione. Objective: The purpose of this study was the development of an efficient and shorter procedure for the synthesis of 21-acetoxypregna-1,4,9(11),16-tetraene-3,20-dione from 9α-hydroxyandrostenedione, which is a product of a bio-oxidative degradation of the side chain of phytosterols. Methods: Pregnane side chain was constructed using cyanohydrin method. For 1(2)- dehydrogenation, selene dioxide was applied for the introduction of Δ1(2)-double bond. Other stages of the synthesis were epimerization, Stork’s iodination procedure and dehydration. Result: 21-Acetoxypregna-1,4,9(11),16-tetraene-3,20-dione was prepared from 9α- hydroxyandrostenedione in yield more than 46%. Conclusion: An efficient and practically feasible procedure for the synthesis of 21-acetoxypregna- 1,4,9(11),16-tetraene-3,20-dione from 9α-hydroxyandrostenedione, a key intermediate for the synthesis of 9-haloidated corticoids, has been developed. The procedure can be applied for the production of value-added 9-haloidated corticoids.

Bioconversion of 16-dehydropregnenolone Acetate to Exclusively 4-androstene-3,17-dione by Delftia acidovorans MTCC 3363

Delftia acidovorans MTCC 3363 was found to convert 16-dehydropregnenolone acetate (16-DPA) exclusively to 4-androstene-3, 17-dione (AD). Addition of 9α-hydroxylase inhibitors was not required for preventing the accumulation of byproducts. The effect of pH, temperature, substrate concentration, surfactants and carrier solvents on this bioconversion has been studied. 16-DPA was maximally converted in buffered medium at pH 7.0, at temperature 30°C and 0.5 mg ml–1 substrate concentration. Detergent addition and temperature above 35°C had deleterious effect on bioconversion. Dioxan was found to be the best carrier solvent for biotransformation of 16-DPA to AD.

One-pot synthesis of chitosan–dehydropregnenolone acetate ketimine nanoparticles and their antifungal bioevaluation

This paper presents a new method for fabricating biodegradable bio-polymeric nanoparticles via a convenient one-pot strategy at room temperature under stirring conditions for application to communicable diseases.

Synthesis of chiral hexacyclic steroids via [8π + 2π] cycloaddition of diazafulvenium methides

16-Dehydropregnenolone acetate reacted with diazafulvenium methides to afford novel chiral 4,5,6,7-tetrahydropyrazolo[1,5-a]pyridine-fused steroids.

Nano-Chromium Trioxide Preparation from Chromium-Containing Waste Liquid Accompanying 16-Dehydropregnenolone Acetate

In polysorbate 80 - alcohol system, Cr2O3 powder had been prepared by using chromium-containing waste liquid from 16-dehydropregnenolone acetate. A precipitation was obtained when water was separated from the wastewater. The nanosample was got after the precipitation was calcined at 250 °C and 600 °C. Cr2O3 powder structure was characterized by FT-IR, SEM and XRD. The results show that the powders are spherical hexagonal system Cr2O3 nanoparticles. The particles size prepared in polysorbate 80 and n-Amyl alcohol system are 50-95 nm. The average value is 78 nm.