Norlignans fromPouzolzia zeylanicavar.microphyllaand their nitric oxide inhibitory activity

Abstract

Five new compounds, pouzolignan F [4-hydroxy-3-(3,5-dihydroxyphenyl)-2-[bis(4-hydroxy-3-methoxyphenyl)methyl]butyl acetate] (1), pouzolignan G [4-hydroxy-3-(3,5-dihydroxyphenyl)-2-[(4-hydroxy-3,5-dimethoxyphenyl)(4-hydroxy-3-methoxyphenyl)methyl]butyl acetate] (2), pouzolignan H [1,4-dihydroxy-3-(3,5-dihydroxyphenyl)-2-[bis(4-hydroxy-3-methoxyphenyl)methyl]butane] (3), pouzolignan I [1,4-dihydroxy-3-(3,5-dihydroxyphenyl)-2-[(4-hydroxy-3,5-dime thoxyphenyl)-(4-hydroxy-3-methoxyphenyl)methyl]butane] (4), and pouzolignan J [1,4-dihydroxy-3-(3,5-dihydroxyphenyl) -2-[(3,4,5-trimethoxyphenyl)(4-hydroxy-3-methoxyphenyl)methyl]butane] (5), along with two known compounds, indolyl-3-carboxylic acid (6) and uracil (7), were isolated from the aerial parts of Pouzolzia zeylanica (L.) Benn. var. microphylla (Wedd.) W.T.Wang. The structures of these compounds were characterized based on spectroscopic methods, including IR, NMR ((1)H-(1)H COSY, HSQC, HMBC, and NOESY), and HR-ESI/TOF-MS experiments. All the new norlignans were assayed for inhibitory activity against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in mouse peritoneal macrophages.

Isolation of lignans and neolignans from Pouzolzia sanguinea with their cytotoxic activity

“…[3] Phytochemical studies on Pouzolzia genus revealed the presence of norlignans, prenylated isoflavones, triterpenes which have shown anti-inflammation and cytotoxic activities. [4,5] In our previous report, several norlignans were identified from aerial parts of P. sanguinea. Their chemical structures were remarkable not only by the loss of one carbon in lignan skeleton but also the presence of an additional benzene ring.…”

Norlignans from the aerial parts of Pouzolzia sanguinea

“…CD3OD,b) 125 MHz, c) 500 MHz; # δC of pouzolignan F, [4] @ δC of pouzolignan G. [4] The molecular formula of 2 was determined to be C27H30O9 by HR-ESI-MS analysis. b) 125 MHz, c) 500 MHz; # δC of pouzolignan H, [4] @ δC of pouzolignan L. [8] 3) and C-4 (δC 65.4) confirmed the appearance of one isoprene moiety. The above mentioned NMR data indicated 2 to be a norlignan, a specific class of compounds of Pouzolia species.…”

“…The above mentioned NMR data indicated 2 to be a norlignan, a specific class of compounds of Pouzolia species. [3, © 2020 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH Verlag GmbH www.vjc.wiley-vch.de 558 4,8] The HMBC correlations between H-1 (δH 3.75 and 4.06)/methyl group (δH 1.87) and carbonyl carbon (δC 172.7) indicated the position of the acetoxy group at C-1. The HMBC correlations between H-2′ (δH 7.04)/H-6′ (δH 6.96) and C-4′ (δC 146.0), H-5′ (δH 6.83)/methoxy protons (δH 3.92) and C-3′ (δC 149.2) suggested the location of the methoxy group at C-3′ and the hydroxy group at C-4′ of phenyl.…”

“…The HMBC correlations between H-2‴/H-6‴ (δH 6.12) and C-3 (δC 48.8); between H-4‴ (δH 6.20) and C-2‴/C-6‴ (δC 108.9) and C-3‴/C-5‴ (δC 159.2) indicated the position of 3,5-dihydroxyphenyl at C-3. Thus, the chemical structure of 2 was elucidated as pouzolignan F. [4] The other compounds were determined as pouzolignan G (3), [4] pouzolignan H (4), [4] and pouzolignan L (5) [8] by comparing their NMR data with those reported in the literature. Compounds 3-5 have been reported from P. zeylanica.…”

“…[1] Chemical investigation of Pouzolzia genus indicated the presence of prenylated isoflavones, norlignans, triterpenes. [2][3][4] In addition, those compounds exhibited the anti-bacterial, antioxidant, and anti-inflammatory activities. [5,6] However, phytochemical and biological studies of P. sanguinea have not been reported yet.…”