Biotransformation of ent-3beta,12alpha-dihydroxy-13-epi-manoyl oxide with Fusarium moniliforme gave the regioselective oxidation of the hydroxyl group at C-3 and the ent-7beta-hydroxylation. The action of Gliocladium roseum in the 3,12-diketoderivative originated monohydroxylations at C-1 and C-7, both by the ent-beta face, while Rhizopus nigricans produced hydroxylation at C-7 or C-18, epoxidation of the double bond, reduction of the keto group at C-3, and combined actions as biohydroxylation at C-2/epoxidation of the double bond and hydroxylation at C-7/reduction of the keto group at C-3. In the ent-3-hydroxy-12-keto epimers, G. roseum originated monohydroxylations at C-1 and C-7 and R. nigricans originated the oxidation at C-3 as a major transformation, epoxidation of double bond and hydroxylation at C-2. Finally, in the ent-3beta-hydroxy epimer R. nigricans also originated minor hydroxylations at C-1, C-6, C-7 and C-20 and F. moniliforme produced an hydroxylation at C-7 and a dihydroxylation at C-7/C-11.
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http://dx.doi.org/10.1016/j.phytochem.2003.09.017 | DOI Listing |
J Colloid Interface Sci
January 2025
School of Chemistry and Chemical Engineering, Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, Guangxi University (GXU), 100 Daxuedong Road, Xixiangtang District, Nanning 530004 China. Electronic address:
Porous carbons with large surface area (>3000 m/g) and heteroatom dopants have shown great promise as electrode materials for zinc ion hybrid capacitors. Centralized mesopores are effective to accelerate kinetics, and edge nitrogen can efficiently enhance pseudocapacitive capability. It is a great challenge to engineer centralized mesopores and edge nitrogen in large-surface-area porous carbons.
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January 2025
Laboratory of Synthesis and Drug Delivery, Department of Biological Sciences, State University of Paraíba, João Pessoa 58071-160, Brazil.
: Leishmaniasis is one of the 20 Neglected Tropical Diseases according to the WHO, affecting approximately 12 million people in four continents, generating serious public health problems. The lack of therapeutic options, associated with toxicity and the emergence of resistance to the few available drugs, makes it urgent to develop new drug options. In this context, the aims of this work are to expand the knowledge about the pharmacophore group responsible for the antileishmanial potential of 2-aminothiophene derivatives.
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Research Group of Environmental and Inorganic Photochemistry, Center for Natural Sciences, Faculty of Engineering, University of Pannonia, P.O. Box 158, H-8201 Veszprém, Hungary.
Graphitic carbon nitride (g-CN) proved to be a promising semiconductor for the photocatalytic degradation of various organic pollutants. However, its efficacy is limited by a fast electron hole recombination, a restricted quantity of active sites, and a modest absorption in the visible range. To overcome these limitations, g-CN-BiS and g-CN-ZnS composites were effectively produced utilizing a starch-assisted technique.
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State Key Laboratory of High-Performance Precision Manufacturing, Dalian University of Technology, Dalian 116024, China.
Laser cladding technology is an effective method for producing wear-resistant coatings on damaged substrates, improving both wear and corrosion resistance, which extends the service life of components. However, the fabrication of hard and brittle materials is highly susceptible to the problem of cracking. Using gradient transition layers is an effective strategy to mitigate the challenge of achieving crack-free laser-melted wear-resistant coatings.
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Graduate Program in Botany, Universidade Federal do Rio Grande do Sul, Porto Alegre 91540-000, Brazil.
Animal density is a grazing management decision implemented by managers that may reduce animal diet quality. Over three years, we collected herd-level cattle samples with varying animal numbers and densities across C grass-legume meadows near Powell, WY, USA. Paddocks ranged in size from 3 to 72 ha, cattle groups ranged from 80 to 370 animals, animal units (AUs; defined as heifers = 0.
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