Use of heterocycles as chiral ligands and auxiliaries in asymmetric syntheses of sphingosine, sphingofungins B and F
作者:Shū Kobayashi、Takayuki Furuta
DOI:10.1016/s0040-4020(98)00484-0
日期:1998.8
prepared from 5 according to standard transformation. The chiral hydrophobic side chain (6) of sphingofungin B was synthesized using a catalytic asymmetric aldol reaction using chiralligand 1-ent. Another keystep in the total synthesis of sphingofungin B was a condensation of chiral aldehyde 7 and chiral heterocycle 2. Similarly, the reaction of chiral aldehyde 8 with heterocycle 3 was a keystep for
Unambiguous synthetic routes to sphingofungins B and F and to their stereoisomers have been developed based on the tin(II)-catalyzed asymmetric aldol reaction (Chiral Lewis Acid-Controlled Synthesis (CLAC Synthesis)). Efficient enantioselective synthesis using a catalytic amount of a chiral source as well as the effectiveness of this strategy for the synthesis of the sphingofungin family have been successfully
基于锡 (II) 催化的不对称醛醇反应(手性路易斯酸控制合成(CLAC 合成)),已经开发了鞘氨醇 B 和 F 及其立体异构体的明确合成路线。使用催化量的手性源进行有效的对映选择性合成以及该策略在合成鞘氨醇家族中的有效性已被成功证明。使用合成的鞘氨醇 B 的立体异构体,揭示了其立体化学与其 SPT 抑制活性的相关性。
Chirality extension of an oxazine building block en route to total syntheses of (+)-hyacinthacine A<sub>2</sub> and sphingofungin B
作者:Seok-Hwi Park、Xiangdan Jin、Jong-Cheol Kang、Changyoung Jung、Seong-Soo Kim、Sung-Soo Kim、Kee-Young Lee、Won-Hun Ham
DOI:10.1039/c5ob00251f
日期:——
achieved via a diastereomerically enriched oxazine intermediate. The key strategies include palladium(0)-catalyzed intramolecular oxazine formation and diastereoselective nucleophilic addition to an aldehyde. (+)-Hyacinthacine A2 was synthesized in 13 steps and 10.2% overall yield and the synthesis of sphingofungin B proceeded in a linear sequence over 15 steps and 6.9% overall yield from (R)-methyl
通过非对映异构体富集的恶嗪中间体可实现立体式控制的(+)-扁豆碱A 2和神经鞘氨醇B的合成。关键策略包括钯(0)催化的分子内恶嗪形成和向醛的非对映选择性亲核加成。(+)-Hyacinthacine A 2的合成步骤为13个步骤,总产率为10.2%,鞘氨醇单糖B的合成以线性顺序进行,历时15个步骤,从(R)-甲基2-苯甲酰胺基-3-(叔丁基二甲基甲硅烷基)氧基)丙酸酯。
METHODS OF TREATMENT, DIAGNOSIS AND MONITORING FOR METHAMPHETAMINE TOXICITY WHICH TARGET CERAMIDE METABOLIC PATHWAYS AND CELLULAR SENESCENCE
申请人:The Regents of the University of California
公开号:US20150148387A1
公开(公告)日:2015-05-28
Methamphetamine is a highly addictive psychostimulant that causes profound damage to the brain and other body organs. Post mortem studies of human tissues have linked the use of this drug to diseases associated with aging, such as coronary atherosclerosis, but the molecular mechanism underlying these findings remains unknown. We report now that methamphetamine accelerates cellular senescence in vitro and activates transcription of genes involved in cell-cycle control and inflammation in vivo by stimulating production of the sphingolipid messenger ceramide. This pathogenic cascade is triggered by reactive oxygen species, generated through methamphetamine metabolism via cytochrome P
450
-2D6, which recruit nuclear factor (NF)-KB to induce expression of enzymes in the de novo pathway of ceramide biosynthesis. Inhibitors of ceramide formation prevent methamphetamine-induced senescence and attenuate systemic inflammation and health deterioration in rats self-administering the drug. The results support therapeutic approaches to reduce the adverse consequences of methamphetamine abuse and improve effectiveness of treatments.
[EN] METHODS OF TREATMENT, DIAGNOSIS AND MONITORING FOR METHAMPHETAMINE TOXICITY WHICH TARGET CERAMIDE METABOLIC PATHWAYS AND CELLULAR SENESCENCE<br/>[FR] PROCÉDÉS DE TRAITEMENT, DE DIAGNOSTIC ET DE SURVEILLANCE DE LA TOXICITÉ DE LA MÉTHAMPHÉTAMINE QUI CIBLENT DES VOIES MÉTABOLIQUES DES CÉRAMIDES ET LA SÉNESCENCE CELLULAIRE
申请人:UNIV CALIFORNIA
公开号:WO2013149250A1
公开(公告)日:2013-10-03
Methamphetamine is a highly addictive psychostimulant that causes profound damage to the brain and other body organs. Post mortem studies of human tissues have linked the use of this drug to diseases associated with aging, such as coronary atherosclerosis, but the molecular mechanism underlying these findings remains unknown. We report now that methamphetamine accelerates cellular senescence in vitro and activates transcription of genes involved in cell-cycle control and inflammation in vivo by stimulating production of the sphingolipid messenger ceramide. This pathogenic cascade is triggered by reactive oxygen species, generated through methamphetamine metabolism via cytochrome Pas0-2D6, which recruit nuclear factor (NF)-KB to induce expression of enzymes in the de novo pathway of ceramide biosynthesis. Inhibitors of ceramide formation prevent methamphetamine-induced senescence and attenuate systemic inflammation and health deterioration in rats self- administering the drug. The results support therapeutic approaches to reduce the adverse consequences of methamphetamine abuse and improve effectiveness of treatments.