Phenylalkyl acids

Animal studies In the study by Pietta et al. (39), a single dose of ginkgo leaf extract (EGb 761) was administered orally to rats. Metabolites found in the urine represented less than 40% of the flavonoids administered. The presence of phenylalkyl acids in the rat urine but not in the human urine (33,39) indicates that the flavonols were more extensively metabolized in humans than in rats. In the study by Watanabe et al. (40), mice received a diet containing ginkgo leaf extract (EGb761 36mg/kg daily) or a standard diet without the extract for four weeks. Afterwards, plasma levels of quercetin (12.0ng/mL vs. 4.8ng/mL), kaempferol (7.0ng/mL vs. 3.2 ng/ mL), and isorhamnetin (49.6ng/mL vs. Ong/mL) in both treatment groups were determined. The study indicates that these compounds can be absorbed intact into the blood stream. 

Alkyl carboxylic acids, as their coenzyme A (CoA) thioesters, are metabolized by oxidation at the (3-xap(3ov to the carboxylic carbon (p-oxidation). This pathway involves the oxidative cleavage of two carbon units at a time (as acetate), beginning at the carboxyl terminus and continuing until no more acetate units can be removed. The reaction is terminated when a branch (e.g., valproic acid) or aromatic group is encountered. The metabolism of even and odd phenylalkyl acids can serve as an example ... 

Another method of preparing ,to-diarylated alkanoic acids utilizes the condensation of 5-(w-phenylalkyl) substituted 2-thiophenealde-hydes (224) with benzyl cyanides and hydrolysis and desulfurization of the acids obtained (225). In this way, a,o-diphenylcaprylic acid has been prepared. ... 

Other aromatic aldehydes and to-phenylalkyl aldehydes react analogously (27). Chloral gives a complex reaction mixture 485), from which 6-phenylguanamine (11%) was isolated. p-Biguanidophenylarsonic acid is said 408) to add one mole of formaldehyde, but the structure of the addition product was not specified. 

In the preparation of a series of phenylalkylphosphonamidate derivatives of glutamic acid, KHMDS was employed to deprotonate the H-P bond in the dibenzyl phosphite, generating a P-nucleophile that reacted with phenylalkyl bromides to provide targeted phosphonates in good yields (eq 73). ... 

Wolf, H.P.O. Engel, D.W. (1985) Eur. J. Biochem. 146, 359-363. Decrease of fatty acid oxidation, keto-genesis, and gluconeogenesis in isolated perfused rat liver by phenylalkyl oxirane carboxylate (B 807-27) due to inhibition of CPT-1 (EC 2.3.1.21). 

Numerous tyrosine hydroxylase inhibitors, chiefly of the phenylalkyl carboxylic acid type, have been described [101,128, 138, 139, 200, 257]. One of the most potent inhibitors in vitro, 3-iodotyrosine, proved inactive in man, probably because it is rapidly dehalogenated in vivo [72]. H22/54 has been found to be one of the most effective tyrosine hydroxylase inhibitors with catechol structure [44, 257]. The pyrroloisoxazole CL-65,263 and its derivatives represent a new type of tyrosine hydroxylase inhibitor [89, 243]. They lower blood pressure and cause... 

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