A new approach to a CD45 protein tyrosine phosphataseinhibitor, pulchellalactam, is described. The key step of the sequence involves addition and elimination of an enolic lactam in a single step and 70% yield, employing an organocuprate reagent. The resulting alpha,beta-unsaturated lactam could be condensed with isobutyraldehyde to produce Z-pulchellalactam or converted into siloxypyrrole, which was
Metal-catalysed radical cyclisations leading to N-heterocycles: new approaches to gabapentin and pulchellalactam
作者:Justin S Bryans、Nicola E.A Chessum、Nathalie Huther、Andrew F Parsons、Franco Ghelfi
DOI:10.1016/s0040-4020(03)01030-5
日期:2003.8
The copper(I) or ruthenium(II)-mediated radical cyclisation of halo-amides has been utilised to afford functionalised pyrrolidinones via 5-endo-trig or 5-exo-trig radical cyclisation pathways. This methodology has been applied to novel and concise syntheses of the anti-epileptic drug gabapentin and the biologically active natural product pulchellalactam.
multicomponent coupling reaction between readily available (Z)‐3‐iodoacrylic acids, terminal alkynes, and primary amines was developed to smoothly access a small library of 5‐hydroxy‐1H‐pyrrol‐2(5H)‐ones in good yields. This practical and general process was applied to a short‐steps synthesis of the natural product pulchellalactam.
Total Synthesis of Pulchellalactam via an RCM Strategy
作者:Subhash P. Chavan、Ashok B. Pathak、Abasaheb N. Dhawane、U. R. Kalkote
DOI:10.1080/00397910701229131
日期:2007.5
Abstract Total synthesis of (Z) pulchellalactam, a CD protein tyrosine phosphatase inhibitor, from commercially available methallylchloride employing ring‐closure metathesis (RCM) as a key step is described.
摘要描述了使用闭环复分解 (RCM) 作为关键步骤从市售的甲基烯丙基氯全合成 (Z) pulchellalactam,一种 CD 蛋白酪氨酸磷酸酶抑制剂。
A Novel Short Approach to (<i>Z</i>)-Pulchellalactam through Transition-Metal-Catalyzed Atom-Transfer Radical Cyclization of 1-Isopropylprop-2-enyl Dichloroacetate
A new, five-step route to (Z)-pulchellalactam, a CD45 protein tyrosine phosphatase inhibitor, is presented. Key steps are the copper(I) chloride-bipyridyl catalyzed atom-transfer radical cyclization of an appropriate allyl α,α-dichloroacetate and the subsequent dehydrochlorination/prototropic rearrangement of the resulting dichlorolactone.