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1.
Chiral [6R and 6S-(6, 9, 10)]methano-1H-cyclooct[b]indol-9-ols were segregated into enantiomers through diastereomeric esters with (R)--trifluoromethylphenylacetic acid. The absolute configuration of the enantiomers was established by the NMR method using the shift reagent Eu(fod)3 and the circular dichroism spectra.  相似文献   

2.
Bis(-hydroxyalkyl) phenylphosphines react with -iminoboranes in protic solvents such as dihydric alcohols to give 2-(l,1-dibutylamyl)-4,6-di-R-5-phenyl-1, 3, 2, 5-dioxaboraphosphorinanes, which react with CuI in pyridine to form [LCuI(Py)] complexes. PMR spectroscopy showed that the phosphorus-containing ligands exist as a single stereoisomer.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 719–723, March, 1991.  相似文献   

3.
By reactions of ,-diamines with 1,2-dihaloethanes there were synthesized ,-bis-N-aziridinoalkanes (la-g) and bis-N-aziridinoethyl ether (II). From 1,3-diaminopropane and dichloroethane bis-aziridine (III) was isolated in addition to (Ia). NMR spectra of the products were studied.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 882–885, April, 1991.  相似文献   

4.
Silica-containing -zirconium phosphate (-ZrSiP) was prepared by the precipitation method. X-ray diffractometry was used to characterize -ZrSiP and to compare it with other -zirconium phosphates (ZrP). A monoclinic cell with parameters of a=0.9038 nm, b=0.529 nm, c=1.4183 nm and =91.76° was identified for -ZrSiP, i.e. silica modifies the original -ZrP structure. The specific surface area of -ZrSiP was found to be two orders of magnitude higher then that of -ZrP.  相似文献   

5.
A new and more effective sequence of reactions is proposed for the production of 16,17-isopropylidenedioxy-5-pregnane-3,21-diol-20-one. It uses methods previously unused for 5-H-steroids and involves 21-hydroxylation of 16,17-epoxy-5-pregnan-3-ol-20-one with diacetoxyiodobenzene and cis-opening of the obtained 21-hydroxy-16,17-epoxy-5-pregnane-3,21-diol-20-one by acetic acid in the presence of epoxycarbonylhydrazine, followed by condensation of the obtained product with acetone.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1185–1188, May, 1991.  相似文献   

6.
For the purpose of preparing pillared materials and multifunctional films,the colloidization and hydrolysis of -Zr(HPO4)2·H2O(-ZrP), -Sn(HPO4)2·H2O (-SnP)and -Ti(HPO4)2·H2O (-TiP) in alkylamineand alcohol amine solutions were investigated. The phosphates colloidizeat a low level of amine intercalation but recrystallize at high levels ofamine uptake. Alcohol amines are more efficient in colloidization ofphosphates than alkylamines, and in the same amine solution -ZrPand -SnP colloidize more readily than -TiP. Thehydrolytic reaction of the phosphates following the course of intercalationin different amine solutions were studied. The dissolution of the metal ionsaccompanying the hydrolysis of HPO42- leads to the destruction ofthe sheet structure. The strong hydrolytic reaction of -TiP causesit to colloidize with difficulty. The phase transformations of the wet amineintercalates during air drying were detected by XRD. The interlayer aminemolecules may arrange in monolayer, bilayer or intermediate orientation,depending on the nature and content of the amines.  相似文献   

7.
Torsional parameters for MM3(96) were derived for the missing atom types present in thenatural product camptothecin (CPT). Potential energy curves were calculated via ab initiocalculations on representative compounds for dihedral angles containing these missingparameters. Gaussian 92 at the restricted Hartree–Fock level of theory using thestandard 6-31G** and 4-31G** basis sets, was used for all the quantum-mechanicscalculations. Missing MM3 torsional terms were obtained by optimizing the V1, V2 and V3parameters such that MM3 could reproduce the ab initio torsional profile. MM3 calculatedmolecular structures that compare well with the ab initio results. Using the newly developedparameters, conformational analyses and QSAR studies of camptothecin analogs wereundertaken. MM3 predicts two distinct boatlike conformations for the -hydroxy lactonemoiety. The low-energy lactone conformation predicted by MM3 is in general agreement withreported X-ray crystal structures of CPT iodoacetate and 7-ethyl-10-(4-piperidino)piperidinylcarbonyloxy CPT HCl as well as the ab initio structure of a CPT-like-hydroxy lactone.  相似文献   

8.
Diazotization of 1-acetyl-S-aminoindoline and reaction of the diazonium salt with ethyl -acetyl--phthalimidovalerate gave the 1-acetyl-5-iruiolhgl hydrazone of ethyl -keto--phthalimidovalerate. Cyclization of the hydrazone and subsequent hydrolysis, decarboxylation, and dehydrogenation of the pyrroloiruloline gave the corresponding tryptamines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 209–212, February, 1994. Original article submitted July 20, 1993.  相似文献   

9.
Summary Using a rapid chemometric methodology to determine the separation factor, , at different temperatures, Gibbs Helmholtz parameters ( (H), (S), (G)) of two adjacent benodiazepines on a chromatogram were obtained from ln versus T–1 plots. A temperature dependent reversal of the elution order was studied and the mobile phase composition and column temperature were optimized to obtain the best separation. A flow rate of 0.80 ml min–1 with 52.6% methanol in the methanol-water mixture and a column temperature of 48°C gave the most efficient separation of ten benzodiazepines.  相似文献   

10.
A differential scanning calorimeter (DSC) was modified for the determination of enthalpies of solution. The measurements were performed on aqueous solutions of the deoxy- and fluoro-deoxy derivatives of D-glucopyranose (Glu) where the OH group on the C1, C2, C3, and C6 is replaced by H (1HGlu, 2HGlu, 3HGlu, and 6HGlu) and by F (1FGlu, 2FGlu, 3FGlu, and 6FGlu), 4-deoxy 4-fluoro--D-glucopyranoside (4FGlu), 1-methoxy--D-glucopyranoside (MeOGlu), 1-phenoxy--D-glucopyranoside (PheOGlu), D-mannopyranose (Man), and 3-methoxy--D-glucopyranoside (3MeOGlu), at 15.1, 25.0, 35.0, and 45.1°C. The enthalpies of solution sH0(T) ranged from 1.00±0.25 kJ-mol–1 for 6HGlu at 15.1°C to 20.4±1.4 for PhOGlu at 45.1°C and were in good agreement with literature values for Man, Glu, MeOGlu, and 3MeOGlu at 25.0 and 35.0°C and for MeOMan and 2HGlu at 35.0°C. sH0(T) for the derivatives were then extrapolated up to the melting temperature Tm and compared with their enthalpies of fusion, fH also determined from DSC measurements. If the agreement between sH0(Tm) and fH was within the 95% confidence level, then it was concluded that intermolecular interactions between the carbohydrate molecules in the liquid phase were the same as between the carbohydrate and water molecules in the solution phase. This agreement was observed for aqueous solutions of Man, Glu, MeOGlu, 3HGlu, 3FGlu, and 6FGlu.  相似文献   

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