3-Hydroxyhexadecanoic acid

The nature of the product strongly depends on the length of the hydroxy acid generally when the hydroxyl group is remote the yield of lactone drops significantly. For example, 10-hydroxydecanoic acid [1679-53-4] does not produce any decanoUde instead, the reaction proceeds by intermolecular oligomerization, and a complex mixture of di-, tri-, tetra-, and pentalactones results (90). However, when Pseudomonas sp. or Candida iylindracea]i 2Lses are incubated with 16-hydroxyhexadecanoic acid [506-13-8] hexadecanoUde is the predorninant product (91). 

Lipase CA also polymerized hydrophobic oxyacids efficiently. The DP value was beyond 100 in the polymerization of 16-hydroxyhexadecanoic acid, 12-hydroxy dodecanoic acid, or 10-hydroxy decanoic acid under vacuum at high temperature (90°C) for 24 h, whereas the polyester with lower molecular weight was formed from 6-hydroxyhexanoic acid under similar reaction conditions. This difference may be due to the lipase-substrate interachon. 

The most common major components of cutin are derivatives of saturated C16 (palmitic) acid and unsaturated C18 acids (Fig. 4). The major component of the C16 family of acids is 9- or 10,16-dihydroxyhexadecanoic acid (and some mid-chain positional isomers), with less 16-hydroxyhexadecanoic acid and much smaller amounts of hexadecanoic acid. In some cases other derivatives are significant constituents. For example, in citrus cutin 16-hydroxy-10-oxo-C16 acid, and in young Vicia faba leaves 16-oxo-9 or 10-hydroxy C16 acid are significant... 

Schneider, S., Wubbolts, M. G., Sanglard, D., and Witholt, B. 1999. Production of alkanedioic acids by cytochrome P450(BM-3) monooxygenase Oxidation of 16-hydroxyhexadecanoic acid to hexadecane-l,16-dioic acid. Biocatalys. Biotransform., 17,163-178. 

E. Votoek and F. Valentin, Rhamnoconvolvulic acid, Collect. Czech. Chem. Comm., 1 (1929) 47-54. F. B. Power and H. Rogerson, Chemical examination of the root of Ipomoea orizabensis, J. Chem. Soc., 101 (1912) 1-26. L. A. Davies and R. Adams, Structures of convolvulinolic and jalapinolic acids. Synthesis of 11-hydroxypentadecanoic and 11-hydroxyhexadecanoic acids, J. Am. Chem. Soc., 50 (1928) 1749-1755. C. Mannich and P. Schumann, Jalap resin and its principal constituents, convolvulin, Arch. Pharm., 276 (1938) 211-226. 

All of the above syntheses resulted in racemic 2-methoxy acids, but the stereospecific synthesis of the naturally occurring (R)-2-methoxyhexadecanoic acid was also recently reported [35]. This synthesis started with commercially available ( )-2-hydroxyhexadecanoic acid for which the S enantiomer was selectively acetylated (47 % yield out of a maximum 50%, > 95% ee) with vinyl acetate in THF using the lipase Pseudomonas Jluorescens from Aldrich, Fig. (14). In order to facilitate the separation of the acetylated acid from the non-acetylated acid, both compounds were methylated with diazomethane, thus avoiding cleavage of the acetate functionality. The methyl (R)-2-... 

Hydroxytetradecanoic acid OH 3-Hydroxytetradecanoic acid OH 16-Hydroxyhexadecanoic acid... 

C16H32O3 16-OH16 0 16-OH16 0 16-Hydroxyhexadecanoic acid Juniperic acid 1909... 

C18H36O6 9,10-OH18 0 9,10-OH18 0 9,10-Hydroxyhexadecanoic acid Dihydroxystearic acid 1925... 

Di hydroam brettol ide 1,16-Hexadecanolactone Hexadecanolide 16-Hexadecanolide 16-Hydroxyhexadecanoic acid lactone Juniperic acid lactone Oxacycloheptadecan-2-one... 

Hydroxy-3,6,9,12,15,18,21 -heptaoxatricos-1-yl dodecanoate. See PEG-8 laurate 23-Hydroxy-3,6,9,12,15,18,21 -heptaoxatricos-1 -yl octadecanoate. See PEG-8 stearate 16-Hydroxyhexadecanoic acid lactone. See Hexadecalactone... 

Oxyacids or their esters were polymerized enzymatically to produce the corresponding polyesters. When using lipase CA, hydrophobic oxyacids were polymerized efficiently [75], with degree of polymerization (DP)-values in excess of 100 for the polymerization of l6-hydroxyhexadecanoic acid, 12-hydroxydodecanoic acid, or... 

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