Hydroxyoctanoate

The methyl ester of 3,7-dimethyl-8-hydroxyoctanoic acid have been prepared in good yields and with ee >98% by deprotonation of the starting trimethyl cyclooctanone 57, R = Me using (R,R) 3 and LiCl at — 78 °C (Scheme 37)77. This reaction is a key step in a versatile synthesis of optically active isoprenoid, which is present as a sub-unit in vitamins, plant metabolites, antibiotics and other naturally occurring compounds. 

C8H1603 8-hydroxyoctanoic acid 764-89-6 23.75 0 9696 2 15592 C8H1804 triethylene glycol monoethyl ether 112-50-5 -18.60 1.2405 2... 

Hydroxyoctanoic acid, H-00363 8-Hydroxyoctanoic acid, H-00364 7-[6-(3-Hydroxy-1 -octenyl)-2,3-... 

Hydroxydecanoic acid, 10-HDAA, ( )-10-hydroxy-2-decenoic acid, 10-HDA [10,16-20] 8-Hydroxyoctanoic acid, 3,12-dihydroxydodecanoic acid, 3,13-dihydroxytetradecenoic acid [10,16-1 8,20]... 

Hydroxyoctanoic acid (2-hydroxycaprylic acid) [617-73-2] M 160.2, m 69.5", b 160-165"/10mm, pK st -3 7. Crystd from EtOH/pet ether or ether/ligroin. 

In order to develop a tissue-engineered heart valve, a group at Children s Hospital in Boston evaluated several synthetic absorbable polyesters as potential scaffolding materials for heart valves. Unfoitu-nately, the most synthetic polyesters proved to be too stiff to be function as flexible leaflets inside a tri-leaflet valve. " In the late 1990s, a much more flexible PHAs called poly-3-hydroxyoctanoate-co-3-hydroxyhexanoate (PHO) was used as the scaffold material for the valve leaflet, and then the entire heart valve. ... 

C) when approximately 12.4% nonafluoro-3-hydroxynonanoate was present in the polymer. The repeating units found in these PH As included trifluoro-3-hydroxybutyrate, heptafluoro-3-hydroxyoctanoate, and nonafluoro-3-hydroxy-nonanoate. The thermal properties and the PHA composition changed with growth time, which indicated that the multi-fluorinated 3HA units were not distributed in the PHA randomly but chains, or chain segments, existed with relatively high multi-fluorinate 3HA units. 

The vast majority of these interesting biopolyesters have been studied and produced only on the laboratory scale. However, there have been several attempts to develop pilot scale processes, and these provide some insight into the production economics of poly(3HAMCL)s other than poly(3HB) and poly(3HB-co-3HV). These processes utilize diverse fermentation strategies to control the monomer composition of the polymer, enabling the tailoring of polymer material properties to some extent. The best studied of these is poly(3-hydroxyoctano-ate) (poly(3HO)), which contains about 90% 3-hydroxyoctanoate. This biopolyester has been produced on the pilot scale and is now being used in several experimental applications. 

Lageveen et al. [41] showed that the monomer composition of aliphatic saturated poly(3HAMCL) produced by P. oleovorans is depended on the type of n-alkane used. It appeared that the n-alkanes were degraded by the subsequent removal of C2-units and it was therefore proposed that the /1-oxidation pathway was involved in poly(3HAMCL) biosynthesis. Preusting et al. [42] confirmed these results but also showed that with hexane as substrate some 3-hydroxyoctanoate and 3-hydroxydecanoate were produced, indicating that additional pathways were involved in poly(3HAMCL) biosynthesis (Table 1). 

C4 = 3-hydroxybutyric acid, C5 = 3-hydroxyvaleric acid, C6 = 3-hydroxyhexanoic acid, C7 = 3-hydroxyheptanoic acid, C8 = 3-hydroxyoctanoic acid, C9 = 3-hydroxynonanoic acid CIO = 3-hydroxydecanoic acid. 

S,4S)-4,8-Diamino-3-hydroxyoctanoic acid (DAHOA) derivatives were synthesized by the route shown in Scheme II using the known aldehyde Boc-Lys(Z)-CH0 (29) and were converted to the DAHOA peptide analogs shown. Inhibition of penicillopepsin by all statine and DAHOA pepstatin analogs was measured using substrate 21. The results of these determinations are shown in Table I. 

Injectable liquid polyhydroxyalkanoate compositions consisting of the transesterification product of poly(3-hydroxyoctanoate-co-3-hydroxyhexanoate) with 1,3-butanediol were prepared by Williams et al. (3) and used in soft tissue repair, augmentation, and viscosupplementation in humans. 

Based on the recent impressive progress made on asymmetric hydrolysis, the design and bio-transformation of the optically active ethyl 2,2-difluoro-3-hydroxyoctanoate 78 and synthesis of optically active fluorinated [6]-gingerol derivatives are reported [82]. The following criteria were used in the search for a practical route to chiral ethyl 2,2-difluoro-3-hydroxyoctanoate with a high -value (1) the search of an additive to enhance the enantioselectivity of asymmetric hydrolysis by lipases, and (2) the modification of ethyl 2,2-difluoro-... 

C,5H,(1C1FN20 17617-60-6) see Cinolazepam 21-chloro-l I (i-hydroxy-1 fifS-methyl-l 7-propionyloxy-prcgn-4-enc-3,20-dione (C H-pCIOj) see Ulobetasol propionate 8-chloro-6-hydroxyoctanoic acid ethyl ester (CI(1H, C10, 1070-65-1) see Thioctic acid 7-chloro-4-(4-hydroxyphenylamino)quinolinc (C llnCIN O 81099-86-7) see Amodiaquinc... 

The best separation of chiral -lactones was reached after derivatization of 4-hydroxyacid esters with R- (+) -phenylethylisocyanate. The oc.-values for the separation of f -hexalactone are given in Table IV. Unfortunately, the oc-values decrease drastically with increasing chain length, so that 4-hydroxyoctanoic acid and the higher homologues could not be separated by this method. 

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