Nitroacetyl Group as a Peptide Synthon: Synthesis of Dipeptides with an ?,?-Bisallylglycine Residue at the N-Terminus
作者:Sulur G. Manjunatha、Pabba Chittari、Srinivasachari Rajappa
DOI:10.1002/hlca.19910740516
日期:1991.8.7
Regiospecific mono- and bis-allylation of these nitroacetyl derivatives were accomplished in presence of a Pd(0) catalyst. The bis-allyl derivatives 7–9 were obtained in 40–75% yield. The tertiary NO2 group in these compounds could be transformed into an acetylamino group by Zn/AcOH/Ac2O. The final products 11–13 are dipeptides in which the N-terminal glycine residue bears two α-allyl substituents.
L-脯氨酸,L-缬氨酸和L-苯丙氨酸酯的N-硝基乙酰基衍生物可在温和条件下分两步制备(方案2)。这些硝基乙酰基衍生物的区域特异性单和双烯丙基化是在Pd(0)催化剂存在下完成的。双烯丙基衍生物7-9以40-75%的产率获得。这些化合物中的叔NO 2基团可以通过Zn / AcOH / Ac 2 O转化为乙酰氨基基团。最终产物11-13是二肽,其中N端甘氨酸残基带有两个α-烯丙基取代基。
Synthesis and metal complexation of chiral 3-mono- or 3,3-bis-allyl-2-hydroxypyrrolopyrazine-1,4-diones
作者:Pabba Chittari、Vasant R. Jadhav、K. Nagappa Ganesh、Srinivasachari Rajappa
DOI:10.1039/a707341k
日期:——
A novel synthesis of chiral cyclic hydroxamic acids (4, 6, 8 and 10) related to cyclodipeptides is described. The crucial reduction of the nitro group of the N-nitroacetyl derivatives of (S)-α-amino acid esters is brought about by zinc–aq. ammonium chloride. The FeIII and CuII complexes of one such cyclic hydroxamic acid 10a have been prepared and their DNAse activity investigated.