Splenectomized patients with hemoglobin (Hb) Köln have rigid RBCs with membrane polypeptide aggregates that are not dissociable with disulfide-reducing agents. Malondialdehyde (MDA) action on normal RBCs produced rigid RBCs with similar nondissociable aggregates. To test the hypothesis that Hb Köln RBC aggregates contained unsaturated MDA-type bonds, we reduced normal control RBC membranes, Hb ...

Complex metal hydrides such as sodium aluminohydride (NaAlH4) and sodium borohydride (NaBH4) are solid-state hydrogen-storage materials with high hydrogen capacities. They can be used in combination with fuel cells as a hydrogen source thus enabling longer operation times compared with classical metal hydrides. The most important point for a wide application of these materials is the reversibil...

The physical properties and the hydrogen release of NaBH4–Mg(BH4)2 and NaBH4−Ca(BH4)2 composites are investigated using in situ synchrotron radiation powder X-ray diffraction, thermal analysis and temperature programmed photographic analysis. The composite, xNaBH4–(1 − x)Mg(BH4)2, x = 0.4 to 0.5, shows melting/frothing between 205 and 220 °C. However, the sample does not become a transparent mo...

Silver colloidal nanorings have been synthesized by reducing silver ions with NaBH4 in trisodium citrate buffers. pH increase, by addition of NaOH, was used to speed up reduction reaction. The UV-vis absorption spectra of resulting silver nanorings showed two peaks accounting for transverse and longitudinal surface plasmon resonance, at ≈400 nm, and between 600 and 700 nm, respectively. The sha...

Positional isomers of naturally occurring peptide subunits were synthesized via highly diastereoselective reduction of tert-butylsulfinyl ketimines as a key reaction. While NaBH4 reduction of ketimines derived from 2-thiazolyl ketones afforded the (RS,R)-isomer with moderate diastereoselectivity, L-Selectride® reduction afforded the (RS,S)-isomer as the sole product. In contrast, ketimines deri...

Reactions of Cp*Ta(NAr)Cl2 and CpM(NAr)Cl2 (M = Nb, Ta; Ar = 2,6-C6H3(i)Pr2) with NaBH4 in the presence of an excess of PMe3 provided facile access to the corresponding dihydride derivatives Cp(R)M(NAr)H2(PMe3) (Cp(R) = Cp, Cp*). Reaction of Cp*Nb(NAr)Cl2 with NaBH4 in the absence of phosphine gave the Nb(+5) borohydride-hydride complex Cp*Nb(NAr)H(η(2)-BH4). When the corresponding reactions fo...