Chiral N-protected β-amino alcohols are easily obtained by NaBH4reduction of mixed anhydrides of N-protected α-amino acids in an organic/aqueous medium. The alcohols obtained from side chain or main chain reduction of N-protected aspartic acid are converted in good yields into lactones.
Synthesis of Thioureido-Linked Peptidomimetics, Glycosylated Amino Acids, and Neoglycoconjugates Using Bis(benzotriazolyl)methanethione as Thioacylating Agent
A practical synthesis of thiourea-linked peptidomimetics, glycosylated amino acids, and neoglycoconjugates is described employing bis(benzotriazolyl)methanethione as thiocarbonylating reagent. The entire protocol is mild, efficient, high-yielding, and free from hazardous reagents. All the intermediates and products have been isolated and fully characterized by ¹H NMR, ¹³C NMR, and mass spectrometry.
A simple approach for the synthesis of new classes of dithiocarbamate-linked peptidomimetics
作者:Hosahalli P. Hemantha、Vommina V. Sureshbabu
DOI:10.1016/j.tetlet.2009.09.172
日期:2009.12
An efficient protocol for the synthesis of a new series of dithiocarbamate-linked peptidomimetics is described. The in situ generated dithiocarbamic acid intermediate formed by the reaction of an aminoacidester and carbon disulfide in the presence of triethylamine was treated with N-protected amino alkyl iodide to afford title compounds 3a–g in good to moderate yields. The synthesis of N-Fmoc-protected
<i>N</i>-Urethane-Protected Amino Alkyl Isothiocyanates: Synthesis, Isolation, Characterization, and Application to the Synthesis of Thioureidopeptides
作者:Vommina V. Sureshbabu、Shankar A. Naik、H. P. Hemantha、N. Narendra、Ushati Das、Tayur N. Guru Row
DOI:10.1021/jo900675s
日期:2009.8.7
Synthetically useful N-Fmoc amino-alkyl isothiocyanates have been described, starting from protected amino acids. These compounds have been synthesized in excellent yields by thiocarbonylation of the monoprotected 1,2-diamines with CS2/TEA/p-TsCl, isolated as stable solids, and completely characterized. The procedure has been extended to the synthesis of amino alkyl isothiocyanates from Boc- and Z-protected amino acids as well. The utility of these isothiocyanates for peptidomimetics synthesis has been demonstrated by employing them in the preparation of a series of dithioureidopeptide esters. Boc-Gly-OH and Boc-Phe-OH derived isothiocyanates 9a and 9c have been obtained as single crystals and their structures solved through X-ray diffraction. They belong to the orthorhombic crystal system, and have a single molecule in the asymmetric unit (Z' = 1). 9a crystallizes in the centrosymmetric space group Pbca, while 9c crystallizes in the noncentrosymmetric space group P2(1)2(1)2(1).
Babu, Vommina V. Suresh; Kantharaju; Sudarshan, Naremaddepalli S., Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 2006, vol. 45, # 8, p. 1880 - 1886
作者:Babu, Vommina V. Suresh、Kantharaju、Sudarshan, Naremaddepalli S.