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Tyrosinase inhibitors from Rhododendron collettianum and their structure-activity relationship (SAR) studies 总被引:1,自引:0,他引:1
Ahmad VU Ullah F Hussain J Farooq U Zubair M Khan MT Choudhary MI 《Chemical & pharmaceutical bulletin》2004,52(12):1458-1461
A new coumarinolignoid 8'-epi-cleomiscosin A (1) together with the new glycoside 8-O-beta-D-glucopyranosyl-6-hydroxy-2-methyl-4H-1-benzopyrane-4-one (2) have been isolated from the aerial parts of Rhododendron collettianum and their structures determined on the basis of spectroscopic evidences. Tyrosinase inhibition study of these compounds and their structure-activity relationship (SAR) were also investigated. The compounds exhibited potent to mild inhibition activity against the enzyme. Especially, the compound 1 showed strong inhibition (IC50=1.33 microM) against the enzyme tyrosinase, as compared to the standard tyrosinase inhibitors kojic acid (IC50=16.67 microM) and L-mimosine (IC50=3.68 microM), indicating its potential used for the treatment of hyperpigmentation associated with the high production of melanocytes. 相似文献
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B. T. Salimov Zh. Kh. Kuzibaeva F. N. Dihakhangirov 《Chemistry of Natural Compounds》1996,32(3):366-368
The toxic and antiarrhythmic activities of diterpene alkaloids fromAconitum zeravschanicum and their synthetic analogs have been investigated. It has been established that, in the series of compounds studied, activity and toxicity depend on the type of skeleton, the nature and positions of substituents, and the basicity of the nitrogen atom.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 384–387, May–June, 1996. Original article submitted February 26, 1996. 相似文献
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The total synthesis of alkaloids phenanthroindolizidine 1a, tylophorine 1b, and phenanthroquinolizidine 1c, has been achieved in 46%, 49%, and 42% overall yield, respectively, starting from the corresponding phenanthrene-9-carboxaldehyde. Compound exhibited potent inhibition activity in three human cancer cell lines, with IC(50) values ranging from 104 to 130 nM. The structure-activity relations of these alkaloids and some of their synthetic intermediates against the three cell lines were also described. 相似文献
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Proposed biogenesis of diterpenoid alkaloids 总被引:2,自引:0,他引:2
Literature information is generalized and an analysis is made of investigations relating to the biogenesis of diterpene alkaloids.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 337–354, May–June, 1995. Original article submitted May 18, 1993. 相似文献
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Otrubova K Styers TJ Pan PS Rodriguez R McGuire KL McAlpine SR 《Chemical communications (Cambridge, England)》2006,(9):1033-1034
Synthesis of twelve Sansalvamide A derivatives and their SAR against colon cancer (HT-29). 相似文献
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The quantitative structure-activity relationships (QSAR) of 2-(4-substituted-1-piperazinyl)benzimidazole derivatives for antihistaminic activity were examined. Taking into consideration the specific conformations of some derivatives, a significant correlation was obtained using Verloop's STERIMOL parameters B3 and L of the substituent at the 1-position of the benzimidazole nucleus. The results indicated that the derivatives having a substituent with a small breadth and an appropriate length at the 1-position showed potent activity. From the results, a model of the binding site is proposed. The QSAR of side effects (anticholinergic activity and central nervous system depressive effect) were also examined and the results showed that a sterically small substituent at the 1-position was required to decrease side effects. 相似文献
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Zinurova E. G. Kabal"nova N. N. Shereshovets V. V. Ivanova E. V. Shults E. E. Tolstikov G. A. Yunusov M. S. 《Russian Chemical Bulletin》2001,50(4):720-723
Oxidation of diterpene alkaloids by dimethyldioxirane was studied with eldeline, talatizamine, aconitine, and zongorine as examples. Nitrones and 19-oxo derivatives of bases were obtained. The results of the oxidation allow one to draw an analogy with the oxidation by KMnO4 and to suggest a mechanism of the reaction. 相似文献
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Kh. M. Shakhidoyatov N. P. Abdullaev Ch. Sh. Kadyrov 《Chemistry of Natural Compounds》1977,13(1):65-68
Summary ,-Bisquaternary salts of the pyrrolizidine series have been synthesized by the reaction of ,-dibromoalkanes with some products of the cleavage of pyrrolizidine alkaloids (lindelofidine, hydroxyheliotridene, and their esters).Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 77–80, January–February, 1977. 相似文献
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The stem bark and wood of Berberis aristata DC (Daruharidra) are one of the principal ingredients of traditional skin lighting and exfoliating scrub preparation in India. The standardised extract of B. aristata was screened to evaluate their in vitro antityrosinase activity and inhibition kinetics. Phytochemical and pharmacological studies were carried out with different solvent fractions of the methanol extract of B. aristata (MEBA). RP-HPLC analysis was used to determine the berberine content in extract and fractions of B. aristata. MEBA showed maximum berberine content. Extract and fractions of B. aristata contain the maximum amount of alkaloids than other constituents. In tyrosinase inhibition assay, MEBA was found to possess highest dose-dependent monophenolase and moderate diphenolase activity. The enzyme kinetic study revealed that MEBA possessed mixed type inhibition of monophenolase activity of tyrosinase. These bioactivities indicate that the MEBA has antihyperpigmentation potential in human skin. 相似文献
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F. N. Dzhakhangirov K. R. Kasymova M. N. Sultankhodzhaev B. T. Salimov S. K. Usmanova R. Sh. Shakirov 《Chemistry of Natural Compounds》2007,43(5):581-589
The toxicity and local anesthetic activity of 74 diterpenoid alkaloids differing in the nature and position of functional
groups in lycoctonine, heteratisine, napelline, hetisane, atisane, and denudatine skeletons and their synthetic derivatives
were investigated. Compounds with local anesthetic activity and duration of action surpassing that of cocaine for surface
anesthesia and that of novocaine and lidocaine for infiltration and trunk administration were identified. Structural factors
affecting the toxicity and local anesthetic activity of the studied compounds were discussed.
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Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 477–484, September–October, 2007. 相似文献
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V. L. Mamedova D. R. Sharafutdinova K. A. Nikitina T. P. Gerasimova O. B. Bazanova V. A. Al’fonsov 《Russian Journal of General Chemistry》2014,84(4):700-703
Metal salts (including transition metals salts) of chiral natural diterpenoid isosteviol and its hydrophosphoryl derivative were obtained for the first time. The compounds obtained can be used in pharmaceutics, metal catalysis, and also for creating new materials with magnetic properties. 相似文献
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新型2-杂环芳基苯并二氢吡喃-4-酮衍生物的三维定量构效关系研究 总被引:1,自引:0,他引:1
为开发新型环境友好杀菌剂,选择了黄烷酮类植物抗毒素为先导,利用生物等排取代原理对其结构进行修饰,设计合成了23个未见文献报道的2-杂环芳基苯并二氢吡喃-4-酮类化合物,并系统测定了所有化合物对水稻稻瘟病抑制活性的IC~5~0值。在此基础上,采用CoMFA方法对它们进行了三维定量结构活性关系研究,系统考查了网格结构、探针以及场类型对CoMFA结果的影响。研究结果表明,苯并二氢吡喃-4-酮苯环5,6,7位上应该引入一些体积较小且具有强供电子能力的取代基有利于提高化合物的杀菌活性。CoMFA分析对7位氧原子和19位氧原子的电性要求与前文采用Hansch-Fujita方法的分析结果是相一致的。 相似文献
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One of the key constituents of the muraymycins is the 6-membered cyclic guanidine, (2S,3S)-muraymycidine (or epi-capreomycidine). In order to diversify the structure of the oligopeptide moiety of the muraymycins for thorough structure-activity relationship studies, we have developed a highly stereoselective synthesis of ureidomuraymycidine derivatives with the lactone 4a. 相似文献