New and simple synthesis of acid azides, ureas and carbamates from carboxylic acids: application of peptide coupling agents EDC and HBTU
作者:Vommina V. Sureshbabu、H. S. Lalithamba、N. Narendra、H. P. Hemantha
DOI:10.1039/b920290k
日期:——
Conversion of carboxylic acids into acid azides using peptide coupling agents, EDC and HBTU is described. The procedure is efficient, practical and applicable to a diverse range of carboxylic acids including N-protected amino acids. Using the same reagents, one-pot synthesis of ureas, dipeptidyl urea esters and carbamates from acids has also been achieved.
Application of carbodiimide mediated Lossen rearrangement for the synthesis of α-ureidopeptides and peptidyl ureas employing N-urethane α-amino/peptidyl hydroxamic acids
作者:N. Narendra、Gundala Chennakrishnareddy、Vommina V. Sureshbabu
DOI:10.1039/b905790k
日期:——
Application of the Lossenrearrangement to the synthesis of N-urethane protected α-peptidyl ureas and ureidopeptides is reported. The carbodiimide mediated rearrangement of N-Boc/Z/Fmoc protected α-amino/peptide hydroxamic acids into isocyanates and coupling of the latter with the amino acid esters/peptide esters have been accomplished in a single-pot to obtain good yields of urea products. Synthesis
报道了Lossen重排在N-氨基甲酸酯保护的α-肽基脲和脲肽的合成中的应用。这碳二亚胺N- Boc / Z / Fmoc保护的α-氨基/肽异羟肟酸介导的重排成异氰酸酯,后者与氨基酸酯/肽酯的偶联已在单罐中完成,从而获得了较高的收率。尿素产品。还已经使用相同的方法经由N-保护的天冬氨酸的异羟肟酸酯衍生物合成脲基丙氨酸衍生物。
Efficient Synthesis of <i>O</i>-Succinimidyl-(<i>tert</i>-Butoxycarbonylamino)methyl Carbamates Derived from α-Amino Acids Accelerated by Ultrasound: Application to the Synthesis of Ureidodipeptides
作者:Vommina V. Sureshbabu、Naremaddepalli S. Sudarshan、Kantharaju
DOI:10.1080/00397910802026386
日期:2008.6.20
The synthesis of O-succinimidyl-(tert-butoxycarbonylamino)methyl carbamates employing isocyanates made through the Curtius rearrangement of Boc-amino acid azides in the presence of N-hydroxysuccinimide under the influence of ultrasound is described.