A sequence of stages in the syntheses of isomeric bisamino acid complexes of Pt(II) with beta-aminopropionic acid (beta-alanine = beta-AlaH) has been studied by the (195)Pt NMR spectroscopy. The techniques have been developed of the synthesis of the cis- and trans-bischelates of Pt(II) and Pd(II) with beta-alanine as well as of the halide complexes of trans-[M(beta-AlaH)(2)Cl(2)] (M = Pt, Pd) a...

The phytochemical analysis of the fresh aerial parts of Portulaca oleracea (Portulacaceae), growing in Jordan, using conventional chromatographic procedures resulted in the isolation of Beta-sitosterol, Beta-sitosterol-glucoside, N,N'-dicyclohexylurea, and allantoin. The last three compounds were isolated for the first time from this plant. The structure elucidation of these compounds was attai...

Factor XIII-cross-linked fragment D (double-D) from human fibrin was crystallized in the presence of two different peptide ligands and the X-ray structure determined at 2.3 A. The peptide Gly-Pro-Arg-Pro-amide, which is an analogue of the knob exposed by the thrombin-catalyzed removal of fibrinopeptide A, was found to reside in the gamma-chain holes, and the peptide Gly-His-Arg-Pro-amide, which...

The structure of 7,8-dihydroxy-4-methylcoumarin was determined by an X-ray diffraction method. The compound crystallized in the triclinic space group P1, Z = 2, with a = 7.631(2), b = 9.456(5), c = 7.075(3)A, alpha = 103.13(3), beta = 91.84(3), gamma= 68.21(3) degrees, and V= 460.9(3)A3. The X-ray crystal structure was also compared with those of 5,7-dihydroxy-4-methylcoumarin and 7-hydroxy-4-m...

The crystal structure of the beta-lactamase of Streptomyces albus G has been solved at 0.3 nm resolution by X-ray-diffraction methods. The enzyme is a typical two-domain protein. One domain consists of five alpha-helices, and the other is five-stranded beta-sheet with alpha-helices on both sides of the sheet. The active-site serine residue (Ser-48) is within a cleft located between the two doma...

The efficiency of the SIR ionization chamber versus photon energy has been obtained by an iterative method, starting from a few monoenergetic gamma-ray emitters. The relative standard uncertainty on the efficiency curve obtained is lower than 10(-2) above 65 keV. An efficiency curve for beta particles has been deduced in a similar manner, from measurements of (quasi-) pure beta emitters. The po...

In this study, beta-In(2)S(3) nanowires were first synthesized by sulfurizing the pure Indium (In) nanowires in an AAO membrane. As FE-SEM results, beta-In(2)S(3) nanowires are highly ordered, arranged tightly corresponding to the high porosity of the AAO membrane used. The diameter of the beta-In(2)S(3) nanowires is about 60 nm with the length of about 6-8 mum. Moreover, the aspect ratio of be...

The three-dimensional structure of a complex of soybean beta-amylase [EC 3.2.1.2] with an inhibitor, alpha-cyclodextrin, has been determined at 3.0 A resolution by X-ray diffraction analysis. Preliminary chain tracing showed that the enzyme folded into large and small domains. The large domain has a (beta alpha)8 super-secondary structure, while the smaller one is formed from two long loops ext...

In this study a complex of naringenin with hydroxypropyl-beta-cyclodextrin (HP-beta-CD) was prepared to improve the hydrophilicity of naringenin. The physicochemical properties of the complex were analyzed by ultraviolet-visible spectrometry (UV), infrared spectrometry (IR), X-ray diffractometry (XRD), differential scanning calorimetry (DSC). The result showed that naringenin had been molecular...

The title compound 4 has been prepared in four steps from ethylglycinate in 63% overall yield. This amino analog of citric acid has been co-crystallized with the class A beta-lactamase BS3 of Bacillus licheniformis and the structure of the complex fully analyzed by X-ray diffraction. Tris-ethyl aminocitrate 3 and the free tris-acid 4 have been tested against a member beta-lactamase from all dis...