Constituents of the Root Wood of Zanthoxylum wutaiense with Antitubercular Activity

Abstract

Bioassay-guided fractionation of the root wood of Zanthoxylum wutaiense led to the isolation of 11 new compounds, wutaiensol methyl ether (1), demethoxywutaiensol methyl ether (2), methyl wutaiensate (3), methyl 7-hydroxyanodendroate (4), methyl 7-methoxyanodendroate (5), wutaifuranol (6), 7-methoxywutaifuranol (7), 7-methoxywutaifuranal (8), methyl wutaifuranate (9), methyl 7-methoxybenzofuran-5-carboxylate (10), and wutaipyranol (12), together with another 37 known compounds, of which one, 7-methoxybenzofuran-5-carboxaldehyde (11), was not previously known as a plant constituent. The structures of these isolates were identified by means of spectroscopic analysis. Five of these isolates were found to be antitubercular constituents, namely, methyl 7-methoxyanodendroate (5), 7-methoxywutaifuranal (8), wutaiensal (13), dictamnine (14), and gamma-fagarine (15), which exhibited antitubercular activity against Mycobacterium tuberculosis H37Rv, showing MIC values of 35, 35, 30, 30, and 30 microg/mL, respectively.

Secondary Metabolites from the Root Wood of Zanthoxylum wutaiense and Their Antitubercular Activity

“…-Zanthoxylum wutaiense Chen (Rutaceae) is an endemic evergreen shrub and distributed in Pingtung County, Taiwan [1]. In a series of studies on the antitubercular constituents of Formosan plants, 1200 species have been screened for antitubercular activity in vitro, and the MeOH extract of the root wood showed antitubercular activity against Mycobacterium tuberculosis H 37 Rv, with a MIC value of 21.2 mg/ml [2]. In previous studies, the root wood of this species had provided several metabolites of benzofurans [2] [3] and benzopyrans [2] with antitubercular activity [2].…”

“…In a series of studies on the antitubercular constituents of Formosan plants, 1200 species have been screened for antitubercular activity in vitro, and the MeOH extract of the root wood showed antitubercular activity against Mycobacterium tuberculosis H 37 Rv, with a MIC value of 21.2 mg/ml [2]. In previous studies, the root wood of this species had provided several metabolites of benzofurans [2] [3] and benzopyrans [2] with antitubercular activity [2]. Careful examination of the minor constituents of the root wood has led to the further isolation of five new compounds, wutaipyranol A (1), 8-methoxywutaipyranol A (2), demethoxywutaiensal (3), demethoxywutaiensol (4), and dihydrodemethoxywutaiensol (5), together with six known compounds.…”

“…The other known isolates, i.e., anodendroic acid (6) [6], wutaialdehyde (7) [2], marmesin (8) [7], 4-methoxy-1-methylquinolin-2-one (9) [8], 4-acetonyl-3,5-dimethoxy-p-quinol (10) [9], and syringaresinol (11) [10], were identified by comparison with authentic samples or literature data.…”

“…Such alkaloids also occur in the Formosan Zanthoxylum species, Z. nitidum [11] [12], Z. integrifoliolum [13], and Z. simulans [14] [15] as reported in our previous studies. However, it is interesting that benzofuran [2] [3] and the benzopyran [2] types of metabolites were abundantly found in the root wood of Z. wutaiense. In addition, methyl 7-methoxyanodendroate, 7-methoxywutaifuranal, methyl demethoxywutaiensate, wutaiensal, 5-(3-hydroxypropyl)-7-methoxybenzofuran, dictamnine, g-fagarine, and valencic acid exhibited antitubercular activities against Mycobacterium tuberculosis H 37 Rv, with MIC values in the range of 30 -50 mg/ml [2].…”

“…However, it is interesting that benzofuran [2] [3] and the benzopyran [2] types of metabolites were abundantly found in the root wood of Z. wutaiense. In addition, methyl 7-methoxyanodendroate, 7-methoxywutaifuranal, methyl demethoxywutaiensate, wutaiensal, 5-(3-hydroxypropyl)-7-methoxybenzofuran, dictamnine, g-fagarine, and valencic acid exhibited antitubercular activities against Mycobacterium tuberculosis H 37 Rv, with MIC values in the range of 30 -50 mg/ml [2]. Compounds 1 -3 also showed MIC values within the similar range as those reported [2].…”