Bolalipid Membrane Structure Revealed by Solid-State 2H NMR Spectroscopy
摘要:
Membranes made from three specifically deuterium-labeled ether-linked bolalipids, [1',1',20',20'-H-2(4)[C(20)BAS-PC, [2',2',19',19'-H-2(4)]C(20)BAS-PC, or [10',11'-H-2(2)]C(20)BAS-PC, were analyzed by H-2 NMR spectroscopy. Unlike more common monopolar, ester-linked phospholipids, C(20)BAS-PC exhibits a high degree of orientational order throughout the membrane and the sn-1 chain of the lipid initially penetrates the bilayer at an orientation different from that of the bilayer normal, resulting in inequivalent deuterium atoms at the C1 position. The approximate hydrophobic layer thickness and area per lipid are 18.4 A and 60.4 A(2), respectively, at 25 degrees C, and their respective thermal expansion coefficients are within 20% of the monopolar phospholipid, DLPC.
Selective Synthesis of α,α-Dideuterio Alcohols by the Reduction of Carboxylic Acids Using SmI2 and D2O as Deuterium Source under SET Conditions
摘要:
The first general method for the chemoselective synthesis of alpha,alpha-dideuterio alcohols directly from feedstock carboxylic acids under single electron transfer conditions using SmI2 is reported. This reaction proceeds after the activation of Sm(II) with a Lewis base, results in excellent levels of deuterium incorporation across a wide range of substrates, and represents an attractive alternative to processes mediated by pyrophoric alkali metal deuterides.
α-dideuterio alcohols from carboxylic acid esters. Sodium dispersions are used as the electron donor in this electron transfer reaction, and ethanol-d1 is employed as the deuterium source. This reactionuses stable, cheap, and commercially available reagents, is operationally simple, and results in excellent deuterium incorporation across a broad range of aliphatic esters, which provides an attractive