Hydroxyphosphinic acids —

Yamagishi, T., Yokonatsu, T., Suemune, K., and Shibuya, S., Enantioselective synthesis of a-hydroxyphosphinic acid derivatives through hydrophosphi-nylation of aldehydes catalyzed by Al-Li-BINOL complex, Tetrahedron, 52, 11725, 1996. 

Similar treatment of 1.1-spiro compounds leads to different results depending upon the number of atoms in the iro ring. The fivemiembered compound 207 a yields the cyclic 2-oxyphosphinic acid ester 208 a (60%) and only 8% of the 4-hydroxyphosphinic acid ester 209a (R = H). Acetic acid ist not necessary for these transformations. 207b and c (R = D, CH3) react in a similar manner ... 

Reaction of olefins with P, Oj and H2O yields /3-hydroxyphosphinic acids in a complex reaction ... 

New y-ethoxycarbonyl- and ot-amino-alkyl-hydroxyphosphinic acid derivatives (366) and (367) were conveniently prepared by Michael addition or Kabachnik-Fields reaction of a new precursor, benzyloxymethyl hydrogen-phosphinate (368), with a,p-unsaturated esters or imines (Scheme 94). " Phosphinic acid inhibitors (369) of Cathepsin C were synthesized by addition of methyl acrylate to the appropriate a-amino phosphinic acid and by... 

The amount of chlonon thus produced is obviously a measure of the amount of acid chloride present in the mixture. The acid is isolated in the form of an insoluble barium salt, the structure of wliich follows from the fact that the acid is monobasic and on boiling with water is converted into the hydroxyphosphinic acid ... 

All the substances 104-110 were evaluated as ATCase inhibitors, using E. coli Histidine-tagged C3 ATCase [100]. All inhibition constants ranging from 190 to 3,600 nM were at least ten times higher than the value of 16 nM of the reference molecule PALA. The best inhibition constant was found for the a-hydroxyphosphinic acid 105 = 190 nM). The cyclic azaphosphinanes 106... 

Diastereoselective reaction of the chiral aldehyde (Fig. 8.3) with diethylphos-phife was mediated by LLB catalytic system (Ln/Li/BINOL) with the diastereoi-somers ratio 75 25, same transformation catalyzed by ALB system gave 80 20 ratio of the diastereoisomers [173]. Synthesized j -amino-a-hydroxyphosphinic acids were considered as key intermediates in the preparation of potential inhibitors of human renin and HIV-protease. 

Yamagishi T, Suemune K, Yokomatsu T, Shibuya S (2002) Asymmetric synthesis of /J-amino-a-hydroxyphosphinic acid derivatives through hydrophosphinylation of a-amino aldehydes. Tetrahedron 58 2577-2583... 

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