Succinoylamino hydroxyethylamino sulfonyl urea derivatives useful as retroviral protease inhibitors
申请人:G.D. Searle & Co.
公开号:US06337398B1
公开(公告)日:2002-01-08
Succinoylamino hydroxyethylamino sulfonyl urea derivatives of the formula:
wherein the substituents are as defined in the specification, are effective as retroviral protease inhibitors, and in particular as inhibitors of HIV protease.
作者:Louis A. Carpino、Dumitru Ionescu、Ayman El-Faham、Petra Henklein、Holger Wenschuh、Michael Bienert、Michael Beyermann
DOI:10.1016/s0040-4039(97)10504-4
日期:1998.1
Although Fmoc amino acid fluorides are excellent reagents for coupling of moderately hindered amino acids (e.g., Aib-to-Aib) they are not suited for significantly more hindered systems (e.g., Aib-to-MeAib). While urethane-protected acid chlorides are inherently more reactive than the fluorides they are also ineffective for hindered systems due to competing oxazolone formation. This limitation is by-passed
N-Silylation of amines and amino acid esters under neutral conditions employing TMS-Cl in the presence of zinc dust
作者:Vommina V. Suresh Babu、Ganga-Ramu Vasanthakumar、Subramanyam J. Tantry
DOI:10.1016/j.tetlet.2005.04.007
日期:2005.6
An expedient synthetic approach to N-silylamines has been developed. The protocol, using TMS-Cl/zinc dust instead of BSA, is useful for the conversion of amines or amino acid esters to the corresponding silyl derivatives, followed by acylation with an acyl chloride or Fmoc-amino acid chloride to give the corresponding amide or peptide. This procedure, affording products in good to excellent yields, is also efficient for the coupling of sterically hindered amino acids like alpha,alpha-dialkylamino acids and NMe-amino acids. Further, the use of an equimolar quantity of organic base, such as Et3N/pyridine, is circumvented. (c) 2005 Published by Elsevier Ltd.