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41.
42.
Anwar Usman Suchada Chantrapromma Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):m45-m47
The title compound, bis(2,4‐dinitrophenolato‐κ2O,O′)(1,4,7,10,13,16‐hexaoxadecane‐κ6O)barium(II), [Ba(C6H3N2O5)2(C12H24O6)], is a 1:1 complex of barium(II)–2,4‐dinitrophenolate and 1,4,7,10,13,16‐hexaoxacyclooctadecane (18‐crown‐6). Its structure is located on a crystallographic inversion centre. The temperature dependence of the crystal structure has been studied. The monoclinic β angle of the P21/n space group increases with increasing temperature. The packing structure of the complex is stabilized by intermolecular C—H?O interactions. 相似文献
43.
Hoong‐Kun Fun Qingli Hao Jiang Wu Xujie Yang Lude Lu Xin Wang Suchada Chantrapromma Ibrahim Abdul Razak Anwar Usman 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):m87-m88
In the structure of the title compound, [CuII(en)2][(EtO)2P(S)S]2 (en is ethylenediamine) or [Cu(C2H8N2)2](C4H10O2PS2)2, the Cu atom lies on a center of inversion and is coordinated in a slightly distorted square coordination geometry by four N atoms from two ethylenediamine molecules. The diethyl dithiophosphate moieties, (EtO)2P(S)S?, act as counter‐anions. 相似文献
44.
Ibrahim Abdul Razak Anwar Usman Hoong‐Kun Fun Bohari M. Yamin Nor Azilah Kasim 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):m162-m164
In the title compound, [Fe(C17H14P)2]2[Sb4Cl16]·C2H6O, the Fe atoms lie on inversion centres and the pairs of cyclopentadienyl rings are consequently in a fully staggered conformation. The centrosymmetric anionic clusters formed by [Sb4Cl16]4? are surrounded by the cations and are held together by weak C—H?Cl interactions. These formations stack along the a axis to form columns, and the columns are interconnected by another weak C—H?Cl interaction along the b axis. 相似文献
45.
Anwar Usman Ibrahim Abdul Razak Hoong‐Kun Fun Suchada Chantrapromma Yan Zhang Jian‐Hua Xu 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(5):o287-o288
In the title compound, C18H13BrClNO3, the heterocyclic ring of the indole is distorted from planarity towards an envelope conformation. The orientations of the indole, oxetane, chloro and bromophenyl substituents are conditioned by the sp3 states of the spiro‐junction and the Cl‐attached C atoms. 相似文献
46.
Anwar Usman Ibrahim Abdul Razak Suchada Chantrapromma Hoong‐Kun Fun Varughese Philip A. Sreekanth M. R. Prathapachandra Kurup 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):o652-o654
The title compound, C16H17N5S, is in the thione form and crystallizes with two independent molecules in the asymmetric unit. In both molecules, the pentamethyleneimine five‐membered ring adopts an envelope conformation, and in one of the molecules this ring shows positional disorder. The thione S and hydrazine N atoms are in the Z configuration with respect to the C—N bond. 相似文献
47.
Anwar Usman Chandini R. Nayar P. A. Unnikrishnan P. B. Sreeja M. R. Prathapachandra Kurup Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(12):o724-o726
The title molecule, C13H13N3O3·H2O, is in the form of a monohydrated zwitterion. The tetrahydropyridinium ring adopts an envelope conformation and is nearly coplanar with the plane of the imidazoline ring. The water solvate molecule plays an important role as a bridge between zwitterions, forming molecular chains running along the c direction, which are interconnected by N—H?O hydrogen bonds into molecular ribbons. The crystal packing is further stabilized by another N—H?O and one O—H?N hydrogen bond, which interconnect the molecular ribbons. 相似文献
48.
A simple, specific, and precise high-performance liquid chromatographic method has been developed for the simultaneous determination of ofloxacin (OFX), tetrahydrozoline hydrochloride (THC), and prednisolone acetate (PAC) in ophthalmic suspension using propylparaben (POP) as the internal standard. The mobile phase consists of 0.05 M phosphate buffer-acetonitrile (65:35, v/v), and the pH is adjusted to 2.7 with orthophosphoric acid. A column containing octadecyl silane chemically bonded to porous silica particles (Waters Spherisorb, 5 microm ODS 1, 4.6 x 150 mm) is used as the stationary phase. The detection is carried out using a variable wavelength UV-vis detector set at 210 nm for OFX and THC and 254 nm for POP (internal standard) and PAC. The solutions are chromatographed at a constant flow rate of 1.2 mL/min. Retention times for OFX, THC, POP, and PAC are approximately 2.5, 4.5, 7.8, and 9.5 min, respectively. The relative retention times are approximately 0.14 min for OFX, 0.35 min for THC, 1.00 min for POP, and 1.22 min for PAC. The linearity range and percent recoveries for OFX, THC, and PAC are 24-120, 4-16, and 16-80 microg/mL and 100.48%, 100.34%, and 100.21%, respectively. 相似文献
49.
Anwar Sadat M. Alam Ashfaq Ahmad Bina Shaheen Siddiqui 《Natural product research》2015,29(24):2291-2294
Ethanol extract of the aerial parts of Bergenia ligulata was subjected to solvent–solvent separation followed by various chromatographic techniques that lead to isolation of bergenine (1), p-hydroxybenzoyl bergenin (2), 11-O-galloylbergenin (3) and methyl gallate (4) as major constituents. Ethyl acetate fraction showed a dose-dependent urease inhibitory pattern with IC50 value of 54μg/mL. Structures of compounds 1 and 3 were established by XRD and 2, 4 by NMR. All these compounds were subjected to DPPH scavenging activity, reducing power assay and urease inhibitory activity. The EC50 7.45 ± 0.2 μg/mL and 5.39 ± 0.28 μg/mL values in terms of antioxidant and reducing power, respectively, were less for 3. Compounds 1–3 showed moderate to significant urease inhibitory potential with IC50 57.1 ± 0.7, IC50 48.4 ± 0.3 and 38.6 ± 1.5. Antioxidant activities and urease inhibitory potential were investigated and compound 3 was found to be the most active. 相似文献
50.
Dr. Jan Nekvinda Michael Kugler Dr. Josef Holub Dr. Suzan El Anwar Dr. Jiří Brynda Klára Pospíšilová Dr. Zdeňka Růžičková Dr. Pavlína Řezáčová Dr. Bohumír Grüner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(69):16541-16553
Carbonic anhydrase IX (CA IX), a tumor-associated metalloenzyme, represents a validated target for cancer therapy and diagnostics. Herein, we report the inhibition properties of isomeric families of sulfonamidopropyl-dicarba-closo-dodecaboranes group(s) prepared using a new direct five-step synthesis from the corresponding parent cages. The protocol offers a reliable solution for synthesis of singly and doubly substituted dicarba-closo-dodecaboranes with a different geometric position of carbon atoms. The closo-compounds from the ortho- and meta-series were then degraded to corresponding 11-vertex dicarba-nido-undecaborate(1−) anions. All compounds show in vitro enzymatic activity against CA IX in the low nanomolar or subnanomolar range. This is accompanied by clear isomer dependence of the inhibition constant (Ki) and selectivity towards CA IX. Decreasing trends in Ki and selectivity index (SI) values are observed with increasing separation of the cage carbon atoms. Interactions of compounds with the active sites of CA IX were explored with X-ray crystallography, and eight high-resolution crystal structures uncovered the structural basis of inhibition potency and selectivity. 相似文献