H-Translocating Membrane-Bound Pyrophosphatase from Fuels Cells via an Alternative Pathway for Energy Generation.

Inorganic pyrophosphatases (PPases) catalyze an essential reaction, namely, the hydrolysis of PP, which is formed in large quantities as a side product of numerous cellular reactions. In the majority of living species, PP hydrolysis is carried out by soluble cytoplasmic PPase (S-PPases) with the released energy dissipated in the form of heat. In part of this energy can be conserved by proton-pumping pyrophosphatase (H-PPase) in the form of a proton electrochemical gradient for further ATP synthesis.

Control of the diastereoselectivity at C(20) in the formation of C(21)-fluorinated thevinols.

A method is reported to control the stereoselectivity at C(20) in the syntheses of 20--21,21,21-trifluorothevinols (12), the opioid ligands incorporating fluorine atoms within the pharmacophore associated with the surroundings of the C(20) carbon atom. The C(20)-alcohols 12 can be prepared either by reaction of 21,21,21-trifluorothevinone (9) with RM (R = alkyl; M = Li, MgX) or by reaction of thevinone (2) and related non-fluorinated ketones with CFSiMe. In general, alcohols 12 were formed as mixtures of the C(20)-epimers, with the major epimers of the alcohols obtained from the aforementioned reactions exploiting RLi CFSiMe with opposite absolute configurations at C(20).