Swerilactones A and B, Anti-HBV New Lactones from a Tradtional Chinese Herb: Swertia mileensis as a Treatment for Viral Hepatitis

Abstract

Swerilactones A (1) and B (2), two novel lactones with an unprecedented 6/6/6/6/6 pentacyclic ring system, were isolated from the traditional Chinese herb of Swertia mileensis with activity against the hepatitis virus. Their structures and relative stereochemistry were elucidated based on spectroscopic methods and further confirmed by X-ray single crystal diffraction analysis. In vitro antihepatitis B virus (HBV) assay on Hep G 2.2.15 cell line showed that compound 1 inhibited HBsAg and HBeAg secretion with IC(50) values of 3.66 and 3.58 mM, respectively.

Naturally Occurring Iridoids and Secoiridoids. An Updated Review, Part 4

“…The antiviral agent 3TC (lamivudine) used as positive control showed inhibitory activity against both HBsAg (IC 50 ϭ17.6 mM, S.Iϭ1.5) and HBeAg secretions (IC 50 : 36.2 mM, SIϽ1). 45) An open label clinical observation study reported that an aqueous extract of the flowering tops of Spanish plant Lamium album along with other two herbs were also used in the treatment of HCV (hepatitis C Virus) infections. 100) For evaluation of active anti-HCV principle from this plant, Zhang et al carried out an anti-HCVpp (HCV pseudoparticles) entry essay on both aqueous and MeOH extracts of the flowering tops of the plant and found activity.…”

Minor secoiridoid aglycones from the low-polarity part of the traditional Chinese herb: Swertia mileensis

“…Interestingly, this investigation resulted in eleven new secoiridoid aglycones including unusual C 9 -skeleton (1-6), bis-C 9 -skeleton (7) and C 10 -skeleton (8)(9)(10)(11) from the low-polarity part of S. mileensis. Structurally, compound 1 belonged to 10-nor-secoiridoid, and compounds 2-6 were attributed to 1-nor-secoiridoids, which further enriched the skeleton types of secoiridoids.…”

“…[8][9][10] As an ongoing search for anti-hepatitis B virus (anti-HBV) active compounds from natural resources, our recent investigation on the active part of S. mileensis resulted in a series of novel lactones, swerilactones A-O and swerilactosides A-C. [11][12][13][14][15][16][17] From a biosynthetic perspective, swerilactones A and B (C 18 skeleton) were derived from two C 9 secoiridoids, and swerilactones H-K (C 29 skeleton) were condensed by two C 10 and one C 9 secoiridoids. In addition, swerilactone G and swerilactosides A and B also contained the characteristic C 9 secoiridoid moieties in their structures.…”

“…Secoiridoids without glycosylation should be present in the low-polarity part of S. mileensis, however this part was ignored in the previous investigation, for its lowcontent and less-activity. Therefore, further investigation was focused on secoiridoid aglycones and was performed on the low-polarity part of S. mileensis, resulting in eleven new (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11), as well as six pre-existing compounds (12)(13)(14)(15)(16)(17). This paper will discuss their isolation, structural elucidation, and anti-HBV properties on HepG 2.2.15 cell line in vitro.…”

Anti-hepatitis B virus active secoiridoids from Swertia kouitchensis

“…2 Its congener plant S. mileensis, well-known as Qing-Ye-Dan in Chinese, has been documented in Chinese Pharmacopoeia (1977-2005 editions) for treatment of viral hepatitis. 3 Our previous investigation on S. mileensis resulted in a series of novel anti-HBV active secoiridoid dimers with C 18 and C 20 skeletons (swerilactones A and B 4 , C and D 5 ) and secoiridoid trimers with C 29 skeleton (swerilactones H-K) 6 , as well as three unusual aromatic lactones (swerilactones E-G) 7 and three new secoiridoid glycoside dimers (swerilactosides A-C) 8 . Presently, xanthones, triterpenoids and sterols except for iridoids have been reported from S. kouitchensis.…”