Actic acid

RAFT polymerization has been used to prepare poly(ethylene oxide)-/ /wA-PS from commercially available hydroxy end-functional polyethylene oxide).4 5 449 Other block copolymers that have been prepared using similar strategies include poly(ethylene-co-butylene)-6/oci-poly(S-eo-MAH), jl poly(ethylene oxide)-block-poly(MMA),440 polyethylene oxide)-Moe -poly(N-vinyl formamide),651 poly(ethylene oxide)-Wot A-poly(NlPAM),651 polyfethylene ox de)-b ock-polyfl,1,2,2-tetrahydroperfluorodecyl acrylate),653 poly(lactic acid)-block-poly(MMA)440 and poly( actic acid)-6focA-poly(NIPAM),4 8-<>54... 

The product of the minimal PKS, 41, is the branch point of the pathway that diverges into a pair of enantio-specific pathways, each of which involves two KRs and affords (-1-)- or (-)-42. The nonactate synthase, NonS, catalyzes the intramolecular Michael addition of (-)-nonactic acid 43a from (-)-42a. A nonS mutant supplemented with ( )-non-actic acid could produce nonactin, monactin, and dinactin, but not trinactin and tetran-actin, which require one/two (-)-homononactate moieties, respectively. This process suggests that NonS can cyclize (-)-42a into (-)-nonactate 43a and (-)-homononactate 35 only and that another nonactate synthase is required for the cyclization of (-b)-42b to give (-l-)-nonactate 43b and (-l-)-homononactate. 

Based on its high sequence homology to CoA ligases, NonL was identified as a CoA ligase catalyzing the transformation of ( )-non-actic acid into ( )-nonactyl CoA. The sequence of reactions for the biosynthesis of nonactin and the other macrotetrolides in S. griseus is shown in Fig. 3 g. 

C3H603 actic acid 50-21-5 3.298 3024 I C4H605 1 malic acid 6915-15-7 4.209... 

Lonvaud-Funel, A. 1999. 1. actic acid bacteria in the quality improvement and depreciation of wine. Ant. van Leeuwen. 76, 317—331. 

Of the two ETarupEXE lacttc acids, that which is optically active is the one accompanying ethylene lactic acid, and predominating over it in amount, in dead muscle it is to this acid that the name par actic acid is most properly applied. It may be obtained from Liebig s meat extract. 

Ps actic acid differs from its two isomeres in that its solutions are dextrogyrous, and the solutions of its salts are Imvogyroua. The specific rotary power of the acid is [ ] = -h3 .6 that of the zinc salt [a] = —7.6 and of the calcium salt (a] = --3 8. Its products of decomposition are the same as those of ordinary lactic acid. 

CO H GlycolBc acid CO.,H l.actic acid HOs Ogit Tartaric acid... 

Gilding DK, Reed AM. Biodegradable polymers for use in surgery polyglycolic/poly(actic acid) homo- and copolymers 1. Polymer 1979 20 1459-64. 

Fig. 49. Molecular Configurations of the Two Optically Active Forms of I.actic Acid...

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