An Efficient Synthesis of Optically Pure N-delta-Monomethylated l-Arginine and l-Ornithine

摘要

N-Methylated l-arginines such as asymmetric dimethyl-l-arginine (ADMA) and monomethyl-l-arginine (NMMA) are well-known endogenous modulators of the nitric oxide (NO) generating system. To understand the (patho)physiological role and impact of N-methylation of l-arginine and l-ornithine an efficient synthesis of the pure enantiomers was needed. A synthetic approach that furnished both the desired amino acids in 8-10 steps from commercially available N-Boc-l-ornithine in good overall yields (20-21%) and with high optical purity (>99% ee) is reported.