Research of metabolic kinetics and reaction phenotyping of ligustrazin by using liver microsomes and recombinant human enzymes was written by Tan, Yan;Zhuang, Xiao-mei;Shen, Guo-lin;Li, Hua;Gao, Yue. And the article was included in Yaoxue Xuebao in 2014.Synthetic Route of C8H12N2O This article mentions the following:
The metabolic characteristics of ligustrazin (TMPz) in liver microsomes were studied. The reaction phenotyping of TMPz metabolism was also identified by in vitro assessment using recombinant human cytochrome P 450 enzymes (CYP) and UDP glucuronosyltransferases (UGT). TMPz was incubated at 37°C with human (HLM) and rat liver microsomes (RLM) in the presence of different co-factors. The metabolic stability and enzyme kinetics of TMPz were studied by determining its remaining concentrations with a LC-MS/MS method. TMPz was only metabolically eliminated in the microsomes with NADPH or NADPH+UDPGA. In the HLM and RLM with NADPH+UDPGA, t1/2, Km, and Vmax of TMPz were 94.24±4.53 and 105.07±9.44 min, 22.74±1.89 and 33.09±2.74μmol·L-1, 253.50±10.06 and 190.40±8.35 nmol·min-1·mg-1 (protein), resp. TMPz showed a slightly higher metabolic rate in HLM than that in RLM. Its primary oxidative metabolites, 2-hydroxymethyl-3,5,6-trimethylpyrazine (HTMP), could undergo glucuronide conjugation. The CYP reaction phenotyping of TMPz metabolism was identified using a panel of recombinant CYP isoforms (rCYP) and specific CYP inhibitors in HLM. CYP1A2, 2C9, and 3A4 were the major CYP isoforms involved in TMPz metabolism Their individual contributions were assessed by using the method of the total normalized rate to be 19.32, 27.79, and 52.90%, resp. It was observed that these CYP isoforms mediated the formation of HTMP in rCYP incubation. The UGT reaction phenotyping of HTMP glucuronidation was also studied preliminarily by using a panel of 6 UGT isoforms (rUGT). UGT1A1, 1A4, and 1A6 were the predominant isoforms mediated the HTMP glucuronidation. The results above indicated that the metabolism of TMPz involves multiple enzymes mediated phase I and phase II reactions. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3Synthetic Route of C8H12N2O).
(3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3) belongs to pyrazine derivatives. Pyrazine has the elements of symmetry for the point group D2h. It has three mutually perpendicular two-fold axes. It also has three mutually perpendicular planes of symmetry. As a result, pyrazine also has a centre of symmetry. Substituted pyrazines have been found as subunits of multiple synthetically constructed therapeutic agents, as well as several natural products.Synthetic Route of C8H12N2O