2150-38-1Relevant articles and documents
Kopsirachin, ein ungewoehnliches Alkaloid aus der Apocynaceae Kopsia dasyrachis Ridl.
Homberger, Katharina,Hesse, Manfred
, p. 237 - 248 (1984)
From the leaves of Kopsia dasyrachis Ridl, a new typ of alkaloid, kopsirachine (1) built up from catechin (2) and skytanthine (3) has been isoled.The structure elucidation is based on spectral and chemical evidence.Oxidative cleavage of its derivative 4 with KMnO4 afforded veratric acid which was identified as its methylester by comparison with an authentic sample.Pyrolysis of 1 yielded δ-skythanthine (3).The stereochemistry of the skythanthine substrituents in 1 could not yet be estabilished.
Tyrosinase Inhibitor from Black Rice Bran
Miyazawa, Mitsuo,Oshima, Teruo,Koshio, Katsuya,Itsuzaki, Yumi,Anzai, Jun
, p. 6953 - 6956 (2003)
The inhibitor of tyrosinase activity in black rice bran was investigated. The methanol extract from black rice bran was re-extracted with hexane, chloroform, ethyl acetate, or water. The ethyl acetate extract had the most potent inhibition against tyrosinase activity by 80.5% at a concentration of 0. 4 mg/mL. Inhibitory compound in the ethyl acetate fraction was isolated by silica gel column chromatography, and identified as protocatechuic acid methyl ester (compound 1) by GC, GC-MS, IR, and 1H and 13C NMR spectroscopy. Compound 1 inhibited 75.4% of tyrosinase activity at a concentration of 0.50 μmol/mL. ID50 (50% inhibition dose) value of compound 1 was 0.28 μmol/mL. To study the structure-activity relationship, protocatechuic acid (2), vanillic acid (3), vanillic acid methyl ester (4), isovanillic acid (5), isovanillic acid methyl ester (6), veratric acid (7), and veratric acid methyl ester (8) were also assayed.
BCL-2 INHIBITOR
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Paragraph 0836-0838, (2021/10/22)
Disclosed herein is a compound of Formula (I) for inhibiting both Bcl-2 wild type and mutated Bcl-2, in particular, Bcl-2 G101V and D103Y, and a method of using the compound disclosed herein for treating dysregulated apoptotic diseases.
Polyhydroxybenzoic acid derivatives as potential new antimalarial agents
Degotte, Gilles,Francotte, Pierre,Pirotte, Bernard,Frédérich, Michel
, (2021/08/07)
With more than 200 million cases and 400,000 related deaths, malaria remains one of the deadliest infectious diseases of 2021. Unfortunately, despite the availability of efficient treatments, we have observed an increase in people infected with malaria since 2015 (from 211 million in 2015 to 229 million in 2019). This trend could partially be due to the development of resistance to all the current drugs. Therefore, there is an urgent need for new alternatives. We have, thus, selected common natural scaffolds, polyhydroxybenzoic acids, and synthesized a library of derivatives to better understand the structure–activity relationships explaining their antiplasmodial effect. Only gallic acid derivatives showed a noticeable potential for further developments. Indeed, they showed a selective inhibitory effect on Plasmodium (IC50 ~20 μM, SI > 5) often associated with interesting water solubility. Moreover, this has confirmed the critical importance of free phenolic functions (pyrogallol moiety) for the antimalarial effect. Methyl 4-benzoxy-3,5-dihydroxybenzoate (39) has, for the first time, been recognized as a potential lead for future research because of its marked inhibitory activity against Plasmodium falciparum and its significant hydrosolubility (3.72 mM).
Synthesis of Some Aromatic and Aliphatic Esters Using WO3/ZrO2 Solid Acid Catalyst under Solvent Free Conditions
Guguloth, Vijaya Charan,Battu, Satyanarayana
, p. 2153 - 2157 (2020/09/16)
A simple method is delineated for the synthesis of substituted ester products in superior yields by esterification reaction under solvent unbound condition using tungsten upgraded ZrO2 solid acid catalyst at 353 K. The WO3/ZrO2 catalyst has been prepared by using impregnation method followed by calcination at 923 K over a period of 6 h in air atmosphere. SEM, XRD, FTIR, and BET surface area techniques were used to categorize this catalyst. Zirconia has both acidic and basic possessions which can be changed by incorporating suitable promoter atom like tungsten which in turn increases the surface area thereby enhancing the surface acidity. Impregnation of W6+ ions exhibits a strong influence on phase modification of zirconia from thermodynamically solid monoclinic to metastable tetragonal phase. Amalgamation of promoter W6+ will stabilize tetragonal phase which is active in catalyzing reactions. In esterification reaction WO3/ZrO2 catalyst was found to be stable, efficient and environmental friendly, effortlessly recovered by filtration, excellent yield of product and can be reusable efficiently.