Aleprolic acid

Aldosterone receptor antagonists, as antihypertensive agents, 5 154t, 159 Ale fermentations, 26 466 Aleprestic acid, 5 36t Alepric acid, 5 36t Aleprolic acid, 5 36t Aleprylic acid, 5 36t Alerting abstracts, in patent literature, 18 223... 

The nonprotein amino acid cyclopentenylglycine (45) is a constituent of the ffee-amino-acid pool in seeds and leaves of Hydnocarpus anthelminthica and Caloncoba echinata (Flacourtiaceae), where it comprises up to 2% of the total free amino acids. This unusual compound is derived via the pathway presented in Fig. 2.18. This amino acid is then converted to cyclopentenylcarboxylic acid (aleprolic acid) (46)... 

The pivotal role of aleprolic acid (cyclopentenylcarboxylic acid) as primer in the biosynthesis of cyclopentenyl fatty acids was examined in a variety of tissues. In seeds of anthelminthica and C. echinata [l- C]aleprolic acid was almost exclusively incorporated into cyclopentenyl fatty acids, and in cells of I. polycarpa suspension cultures at a level of well over 60% (Cramer and Spener, 1976 Buchholz and Spener, 1980). In the cell cultures used, where endogenous cyclopentenyl fatty acids occurred only at a minor level, the substrate was taken up and activated for both anabolic and catabolic reactions. The acetate thus formed was refunneled and used for the de novo synthesis predominantly of straight-chain fatty acids (Buchholz and Spener, 1980). 

Administration of [l- C]aleprolic acid to chopped leaves of H. anthelminthica and C. echinata showed that most of the substrate was also catabolized. When subcellular fractions devoted mainly to catabolic events were removed, [l- C]aleprolic acid supplied to chloroplasts primed the synthesis of cyclopentenyl fatty acids only (Rehfeldt et al., 1980). 

The introduction of a double bond into the aliphatic chain, i.e., the desaturation of monounsaturated cyclopentenyl fatty acids, is oxygen-dependent, and its mechanism resembles that for straight-chain fatty acids. After administration of [l- C]aleprolic acid to H. anthelminthica seeds, as well as to C. vulgaris, the ratio of mono- to diunsaturated cyclopentenyl fatty acids synthesized greatly increased under anaerobic conditions (Spener, 1975). 

The main occurrence of cyclopentenyl fatty acids in seeds of Flacourtia-ceae suggests a function as an eneigy reserve to be utilized during germination. The degradability of these alicyclic acids by endogenous enzymes can be deduced from indirect evidence. In the course of jS-oxidation, aleprolic acid must be formed as an intermediate. It has been shown that exogenously added [l- C]aleprolic acid is readily catabolized (Cramer and Spener, 1976). 

Fig. 4. Structures of cyclopentenyl fatty acids. Homologues of chaulmoogric acid, CsHt—(CH,)n—COOH, are, withn = 0, 2, 4, 6, 8, 10, 14, aleprolic, alepraic, aleprestic, alepry-lic, alepric, hydnocarpic, and hormelic acids, respectively. A homologue of gorlic acid is onco-bic acid, 15-(2 -cyclopentenyl)-8-pentadecenoic acid.

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