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Jzsef Deli Erzsbet
sz Júlia Visy Ferenc Zsila Mikls Simonyi Gyula Tth 《Helvetica chimica acta》2001,84(1):263-270
The (3R,5′R,6′R)‐ and (3R,5′R,6′S)‐capsanthol‐3′‐one (=3,6′‐dihydroxy‐β,κ‐caroten‐3′‐one; 4 and 5 , resp.) were reduced by different complex metal hydrides containing organic ligands. The ratio of the thus obtained diastereoisomeric (3′S)‐capsanthols 2 and 3 or (3′R)‐capsanthols 6 and 7 , respectively, was investigated. Four complex hydrides showed remarkable stereoselectivity and produced the (3′R,6′S)‐capsanthol ( 6 ) in 80 – 100% (see Table 1). The starting materials and the products were characterized by UV/VIS, CD, 1H‐ and 13C‐NMR, and mass spectra. 相似文献
54.
Pter Molnr Jzsef Deli Zoltn Matus Gyula Tth Dorte Renneberg Hanspeter Pfander 《Helvetica chimica acta》2000,83(7):1535-1541
Cucurbitaxanthin A (=(all‐E,3S,5R,6R,3′R)‐3,6‐epoxy‐5,6‐dihydro‐β,β‐carotene‐5,3′‐diol; 1 ) was submitted to thermal isomerization and to I2‐catalysed photoisomerization. The structure of the main reaction products (9Z)‐ ( 2 ), (9′Z)‐ ( 3 ), (13Z)‐ ( 4 ), and (13′Z)‐cucurbitaxanthin A ( 5 ) was determined by their UV/VIS, CD, 1H‐NMR, and mass spectra. 相似文献
55.
Jzsef Deli Pter Molnr Zoltn Matus Gyula Tth Andrea Steck Urs A.Niggli Hanspeter Pfander 《Helvetica chimica acta》1998,81(10):1815-1820
From the pollens of Aesculus hippocastanum, a new apocarotenoid was isolated as the main carotenoid and, based on the spectroscopic data, identified as (all-E,3R)-3-hydroxy-6′-apo-β-caroten-6′-al ( 4 , aesculaxanthin). In addition, (all-E)-lutein ( 3 ) and (all-E)-β-citraurin ( 5 ) were isolated. Furthermore, 6 (aesculaxanthol) was prepared by reduction of 4 with NaBH4 and tentatively identified as natural carotenoid. 相似文献
56.
Pter Molnr Erzsbet sz Ferenc Zsila Mikls Simonyi Jzsef Deli 《Helvetica chimica acta》2002,85(8):2349-2357
Partially acetylated carotenoids were prepared from fully acetylated carotenoids by reaction with NaBH4, and were characterized by UV/VIS, CD, 1H‐NMR and mass spectra. The 3,6′‐diacetate, 3′,6′‐diacetate, and 6′‐acetate 10 – 12 , respectively, of (6′R)‐capsanthol (=(3R,3′S,5′R,6′R)‐β,κ‐carotene‐3,3′,6′‐triol; 4 ) were obtained from (6′R)‐capsanthol‐3,3′,6′‐triacetate ( 9 ), and the 3‐ and 3′‐acetates 13 and 14 , respectively, of 4 from (6′R)‐capsanthol 3,3′‐diacetate ( 8 ). The utility of this method was also demonstrated by the preparation of zeaxanthin and lutein monoacetates 16, 19 , and 20 . 相似文献
57.
Saad Alkaade Rana Fattahi N. Cem Balci E. Isin Akduman Paul J. Garvin Kian Ali Modanlou Frank R. Burton 《Magnetic resonance imaging》2009,27(7):1005-1008
Peripancreatic fluid collections are among the common post pancreas transplant complications, which are mainly due to leakage from the anastomosis site to bowel and graft pancreatitis. Differentiation between these two entities is important because they are treated differently.In this case, secretin stimulated magnetic resonance cholangiopancreatography revealed gradual intraperitoneal fluid collection and accumulation of fluid in small bowel excluded leakage from the anastomosis of the pancreas to bowel and changed the management from surgery to medical treatment. 相似文献
58.
Cem Cüneyt Ersanl Mustafa Odabaolu Uur Sar Ahmet Erdnmez 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(4):o243-o245
The title compound [systematic name: 2‐cinnamoyl‐1,2‐benzisothiazol‐3(2H)‐one 1,1‐dioxide], C16H11NO4S, contains both saccharin and cinnamoyl groups. The molecule is approximately planar in the solid state, and adjacent molecules are connected by C—H·O and C—H·π(phenyl) interactions. In the C—H·π interaction, the C·CgA distance is 3.916 (4) Å (CgA is the non‐fused benzene ring centroid) and the C—H·π angle is 156 (2)°. A feature of the molecular geometry is the narrow C—S—N angle of 92.51 (9)° in the five‐membered ring. This angle relieves strain from the ring and makes it possible for the whole saccharin group to become quite planar. 相似文献
59.
Günseli Turgut Metin Zora Mustafa Odabaolu Cem Cüneyt Ersanl Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(5):o321-o323
The crystal structure of the title compound, C2H10N2O2+·2Cl−, is built up from one 2‐hydroxyethylhydrazinium(2+) cation and two Cl− anions. The molecular structure is stabilized by O—H⋯Cl and N—H⋯Cl hydrogen bonds. The crystal structure is stabilized by one N—H⋯O and three N—H⋯Cl interactions, and the three‐dimensional network of hydrogen bonds stabilizes the crystal packing. All five hydrazinium H atoms are involved in hydrogen bonds to Cl− anions. The Cl⋯H contact distances range from 2.122 (15) to 2.809 (14) Å. 相似文献
60.
Cem Cüneyt Ersanl idem Albayrak Mustafa Odabaolu Carsten Thne Ahmet Erdnmez 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o133-o135
The structure of the title compound, C18H20ClN3O5, displays the characteristic features of azobenzene derivatives. Intramolecular N—H⋯O, weak intramolecular C—H⋯O, and intermolecular O—H⋯O and C—H⋯O interactions influence the conformation of the molecules and the crystal packing. Intermolecular hydrogen bonds link the molecules into infinite chains, and the title compound adopts the keto–amine tautomeric form. The azobenzene moiety of the molecule has a trans configuration. The molecule is not planar, and the dihedral angle between the two phenyl rings is 35.6 (2)°. 相似文献