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methodology for distinguishing the similar basic sites in spermidine has led to the first synthesis of thermospermine . 相似文献
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Anwar Usman Ibrahim Abdul Razak Suchada Chantrapromma Hoong-Kun Fun Jayanta Kumar Ray Sujit Das Adhikari Bishnu Pada Datta 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(12):1441-1442
In the title compound, C20H20FNO5S, the pyrrolidine ring adopts an envelope conformation. The fluorophenyl and thiophene rings are individually planar. The molecular and crystal structures are stabilized by intra- and intermolecular C—H⋯O interactions. 相似文献
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The active constituent of “jikoppi,” a clinically effective Oriental medicine for hypertension, has been synthesized from spermine using new methodology for polyamine alkylation. 相似文献
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Two new rocaglamide derivatives, 1-O-formylrocagloic acid (1) and 3'-hydroxy rocagloic acid (2), together with five known compounds, rocaglaol (3), rocagloic acid (4), 3'-hydroxymethylrocaglate (5), 1-O-formylmethyl rocaglate (6), and methylrocaglate (7), were isolated from the fruits of Amoora cucullata. Their structures were elucidated by spectroscopic methods. Compounds 1-3, 6, and 7 exhibited potent cytotoxicity against KB, BC, and NCI-H187 cell lines, whereas 4 and 5 showed selective cytotoxicity against NCI-H187 cell line. 相似文献
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Laphookhieo S Syers JK Kiattansakul R Chantrapromma K 《Chemical & pharmaceutical bulletin》2006,54(5):745-747
A new prenylated xanthone, 5-O-methylcelebixanthone (1), together with six known compounds; celebixanthone (2), 1,3,7-trihydroxy-2,4-di(3-methylbut-2-enyl)xanthone (3), cochinchinone A (4), alpha-mangostin (5), beta-mangostin (6) and cochinchinone C (7) were isolated from roots of Cratoxylum cochinchinense. Their structures were elucidated by spectroscopic methods. Compounds 2 and 4-7 showed cytotoxic activity against the human lung cancer cell line (NCI-H187) with IC(50) values ranging from 0.65 to 5.2 microg/ml. Compounds 1, 2, 6 and 7 also showed antimalarial activity against Plasmodium falciparum with IC(50) values of 3.2, 4.9, 7.2 and 2.6 microg/ml, respectively. 相似文献
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K. Chantrapromma S. Chantrapromma R. Suttirak P. Ruanwas N. Boonnak H.-K. Fun 《Crystallography Reports》2017,62(7):1071-1077
A synthetic route involving 4,6-dimethoxy-2-hydroxy-3-methylbenzoic acid (10) and 2,4-dimethoxy-6-hydroxy-3-methylbenzoic acid (11) has been investigated in the process of synthesis of the natural lichen substance namely, crocynol. Crystal structures of 10 and 11 were determined to confirm the ambiguous structures of the two isomers. Crystals 10 are monoclinic, sp. gr. P21/m, Z = 2. Crystals 11 are monoclinic, sp. gr. P21/c, Z = 4. In the crystal packing of 10, the molecules are arranged into chains along the a-axis formed only by van der Waals interactions, whereas in 11, the molecules are linked by O–H···O and C–H···O hydrogen bonds into chains along the b-axis and further stacked by π···π interactions with the centroid ···centroid distance of 3.6863(8) Å. 相似文献
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S. Kannan S. Chantrapromma H. K. Fun S. Robinson Jebas 《Journal of chemical crystallography》2009,39(1):9-12
Abstract The crystal structures for two of the ligands C6H5CH2SOCH2CONHCH2C6H5 (1) and C6H5SOCH2CON(iC3H7)2 (2) have been determined by X-ray diffraction. These compounds crystallize in orthorhombic system with space groups and cell
parameters, Pca21(no. 29), a = 8.4600(5) ?, b = 5.3534(5) ?, c = 32.136(2) ?, V = 1455.42(15) ?3 and Pna21(no. 33) a = 17.5563(11) ?, b = 5.7902(4) ?, c = 14.2866(9) ?, V = 1452.30(16) ?3, respectively. These molecules are stabilized in solid state by various intra and intermolecular hydrogen bonding interactions
to give polymeric structures. The reported IR spectra of these compounds in solid state could be explained on the basis of
the observed intermolecular hydrogen bonding interactions.
Index Abstract The title compounds C6H5CH2SOCH2CONHCH2C6H5 (1) and C6H5SOCH2CON(iC3H7)2 (2) were prepared by the oxidation of corresponding sulfides with H2O2/SeO2 in methanol and their structures were determined. The structures show that the SO and CO groups are having “anti” configuration
in 1 and “syn” configuration in 2.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献