Pradefovir: A Prodrug That Targets Adefovir to the Liver for the Treatment of Hepatitis B
摘要:
Adefovir dipivoxil, a marketed drug for the treatment of hepatitis B, is dosed at submaximally efficacious doses because of renal toxicity. In an effort to improve the therapeutic index of adefovir, 1-aryl-1,3-propanyl prodrugs were synthesized with the rationale that this selectively liver-activated prodrug class would enhance liver levels of the active metabolite adefovir diphosphate (ADV-DP) and/or decrease kidney exposure. The lead prodrug (14, MB06866, pradefovir), identified from a variety of in vitro and in vivo assays, exhibited good oral bioavailability (F = 42%, mesylate salt, rat) and rate of prodrug conversion to ADV-DP. Tissue distribution studies in the rat using radiolabeled materials showed that cyclic 1-aryl-1,3-propanyl prodrugs enhance the delivery of adefovir and its metabolites to the liver, with pradefovir exhibiting a 12-fold improvement in the liver/kidney ratio over adefovir dipivoxil.
An efficient, economical, and practical Reformatsky reaction of α-halo carbonylcompounds with aldehydes/ketones by using cheap and commercial iron(0) powder as reaction mediator is developed. The reactions proceeded effectively in the presence of a catalytic amount of iodine (20 mol %) to afford the synthetically useful β-hydroxyl carbonylcompounds in moderate to good yields.
hemimalonate used. With the unsubstituted substrate, a carboxylic acid intermediate was isolated upon acid quench resulting from the nucleophilic addition of the putative enol carboxylate anion of the hemimalonate to imines/aldehydes before CO2 loss. With substituted hemimalonates, the reaction likely involved an enolate which then added to imines/aldehydes or was competitively protonated. According to the base
compounds screened for activity, 9 phenylpropanoates, 3 cinnamates, and 4 benzoates were found to be highly active antifeedants. To understand the structure-activity relationships of these compounds, a multivariate analysis study was performed. A number of molecular and substituent descriptors were calculated and correlated to results from two-choice feeding tests with H. abietis. Three local models were developed
Optically active alkyl 3-aryl-3-hydroxypropionates and a method for producing thereof
申请人:CHISSO CORPORATION
公开号:EP0451668A2
公开(公告)日:1991-10-16
The invention relates to optically active alkyl 3-aryl-3-hydroxypropionates represented by the general formula:
wherein R¹, R², R³, R ⁴ and R⁵ are hydrogen, hydroxyl, alkoxy of 1-4 carbon atoms, benzyloxy, flurorine, chlorine or bromine and R⁶ is alkyl,
and a method for producing the above compounds.