[Identification of metabolites of antitumor lead compound T-OA in rat urine by HPLC-HRMS].

Objective: To study the major metabolites of antitumor lead compound T-OA (oleanolic acyl-3, 5, 6-trimethyl pyrazine-2-methyl ester) in rat urine, in order to preliminarily infer its metabolic mode in rats.

Method: Rat urines of the blank group, the raw material group (ligustrazine TMP and oleanolic acid OA Moore equivalent) and the T-OA group were collected and freeze-dried; Solids were extracted by ethyl acetate; And then the extracts were re-dissolved with acetonitrile. HPLC-HRMS coupling technique was adopted to find the potential mass spectrum peak under ESI(+) (see symbol) ESI(-) modes. Metabolite-related information was obtained by comparing the three groups of spectra.

Result: One metabolite of OA and two metabolites of TMP were identified in the raw material group; none metabolite of T-OA but one phase II metabolite was detected in the T-OA group.

Conclusion: It is the first time to identify one phase II metabolite of T-OA and one phase II metabolite of OA were identified in rat urine. On that basis, the researchers preliminarily inferred that T-OA does not show the efficacy in the form of raw material. The HPLC-HRMS method established could be used to identify metabolites of related derivative structures. This paper could also provide certain reference for designing pro-drugs based on oleanolic acid.