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Santalova E.A.,RAS Pacific Institute of Bioorganic Chemistry
Natural Product Communications | Year: 2012

Treatment of 3,5-dibromoverongiaquinol (1) with NaHCO3-MeOH at room temperature gave cavernicolin-1 (2), cavernicolin-2 (3), the 4,7-dimethoxy analogue of subereatensin (4) and dimethyl ketal (5). These transformations may clarify the origin of the cavernicolins and subereatensin isolated from the extracts of some verongid sponges.

Utkina N.K.,RAS Pacific Institute of Bioorganic Chemistry
Natural Product Communications | Year: 2013

Antioxidant activities of zyzzyanones A-D (1-4) and makaluvamines C (8), E (5), G (6), H (9), and L (7) isolated from the marine sponge Zyzzya fuliginosa (Carter, 1879) were evaluated using 2,2'-azinobis(3-ethylbenzothiazoline-6- sulfonate) (ABTS) scavenging assay and AAPH (2,2'-azobis(2-amidinopropane) dihydrochloride) induced autoxidation of linoleic acid. Zyzzyanones A, B (1, 2; TE = 0.3), C, D (3, 4; TE = 0.24) and makaluvamines 5-7 (TE = 0.6) displayed moderate activities in the ABTS assay and in the autoxidation of linoleic acid (61-66 % inhibition at concentrations of 0.1 mM). Makaluvamines C (8) and H (9) were essentially inactive in the both assays. Structure-activity relationships showed that antioxidant activities of tested compounds depended on the presence of a phenolic function in molecules. Makaluvamines 5-7 possessing a p-hydroxystyryl moiety were more active than zyzzyanones 1-4 possessing a p-hydroxyphenyl fragment. The presence of a charged side chain in 1 and 2 slightly increases their ABTS scavenging activity in comparison with compounds 3 and 4. Structural variations in a pyrroloquinoline skeleton of 5-7 and in a dipyrroloquinone core of 1-4 have no effect on activities.

Evtushenko E.V.,RAS Pacific Institute of Bioorganic Chemistry
Carbohydrate Research | Year: 2012

Benzoylation of methyl and benzyl glycopyranosides by benzoic anhydride in acetonitrile in the presence of copper(II) trifluoroacetate as a promoter has given monobenzoates with a good yield and high regioselectivity. The composition of monobenzoates depended both on a configuration of hydroxyl groups and on a configuration of aglycone. The simple syntheses of the monobenzoates of some glycosides are offered. © 2012 Elsevier Ltd. All rights reserved.

Bulgakov V.P.,Russian Academy of Sciences | Inyushkina Y.V.,Russian Academy of Sciences | Fedoreyev S.A.,RAS Pacific Institute of Bioorganic Chemistry
Critical Reviews in Biotechnology | Year: 2012

Rosmarinic acid (RA) is one of the first secondary metabolites produced in plant cell cultures in extremely high yields, up to 19% of the cell dry weight. More complex derivatives of RA, such as rabdosiin and lithospermic acid B, later were also obtained in cell cultures at high yields. RA and its derivatives possess promising biological activities, such as improvement of cognitive performance, prevention of the development of Alzheimer's disease, cardioprotective effects, reduction of the severity of kidney diseases and cancer chemoprevention. The TNF-α-induced NF-κB signaling pathway has emerged as a central target for RA. Despite these impressive activities and high yields, the biotechnological production of these metabolites on an industrial scale has not progressed. We summarized data suggesting that external stimuli, the Ca2-dependent NADPH oxidase pathway and processes of protein phosphorylation/dephosphorylation are involved in the regulation of biosynthesis of these substances in cultured plant cells. In spite of growing information about pathways regulating biosynthesis of RA and its derivatives in cultured plant cells, the exact mechanism of regulation remains unknown. We suggest that further progress in the biotechnology of RA and its derivatives can be achieved by using new high-throughput techniques. © 2012 Informa Healthcare USA, Inc.

Evtushenko E.V.,RAS Pacific Institute of Bioorganic Chemistry
Journal of Carbohydrate Chemistry | Year: 2015

Benzoylation of 4,6-O-benzylidene acetals of glycopyranosides by benzoic anhydride in acetonitrile in the presence of Cu(CF3COO)2 as a promoter gave 2-benzoates for α-D-glucopyranosides and α-D-mannopyranosides and 3-benzoates for β-D-galactopyranosides in good yields with high regioselectivity. Benzoylation of 4,6-O-benzylidene acetals of glycopyranosides of D-galactose and D-mannose by benzoyl chloride in the presence of MoO2(acac)2 as a catalyst in all studied cases led to regioselective 3-substitution. © 2015 Taylor and Francis Group, LLC.

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