Isolation and structure elucidation of 12beta-acetoxycoccinic Acid, 12beta-hydroxycoccinic Acid, 12alpha-acetoxycoccinic Acid, and 12alpha-hydroxycoccinic acid1

A review of the phytochemistry and pharmacology of Kadsura heteroclita, an important plant in Tujia ethnomedicine

ETHNOPHARMACOLOGICAL RELEVANCE

Kadsura heteroclita (Roxb.) Craib (traditionally known as "Xue Tong") is an important member of the economically and medicinally important plant family Schisandraceae. "Xue Tong" is an imperative ingredient of the Tujia ethnomedicine, traditionally used for the treatment of rheumatoid arthritis (RA), hepatitis, and muscles and joint spasm. The plant is known to be a rich source of lignans and triterpenoids. These classes of natural products have been known to possess various pharmacological activities.

AIM OF REVIEW

This review was motivated by the importance of K. heteroclita in traditional Chinese medicine (TCM). It aims to compile the available information on its botanical distribution and description, traditional uses, phytochemistry, pharmacological activities, toxicity, and quality control to provide a solid base for further research and development.

MATERIALS AND METHODS

Relevant literature was collected by several scientific databases including PubMed, CNKI, Scifinder, The Plant List, Google Scholar, Baidu Scholar, Books (Tujia pharmaceutical records, Guangxi Chinese herbal medicine, Hunan pharmaceutical records and Field identification manual of Chinese herbal medicine) and other literature sources (Flora of China, Pharmacopoeia of the People's Republic of China) which helped in collecting maximum data about the studied species.

RESULTS

Traditional uses of K. heteroclita have proven its medicinal importance, providing a rationale for scientific research. Phytochemical studies on the stem of K. heteroclita resulted in the identification of 187 chemical constituents, among which lignans and triterpenoids are the predominant groups. The isolates and crude extracts have been found to exhibit a wide spectrum of in vivo and in vitro pharmacological activities such as anti-RA, anti-inflammatory and analgesic, hepatoprotection, anti-HIV, anti-cancer and anti-HBV. Schisanlactone E (xuetongsu), a triterpenoid, is one of the major components of K. heteroclita exhibiting anti-cancer, neuroprotective and anti-neuroinflammation activities. Interestingly and luckily, this plant has been found to be safe and non-toxic within the therapeutic dose range.

CONCLUSION

Pharmacological investigations have validated the use of K. heteroclita in traditional Chinese medicine (TCM). Literature review has demonstrated that lignans and triterpenoids are possibly responsible for most of the biological activities exhibited by this plant. To conclude, this plant shows immense potential for the discovery of more potent bioactive secondary metabolites and therefore further phytochemical and biological studies on other parts of K. heteroclita need to be conducted and more compounds need to be tested regarding their biological activities to completely explore its value as a tremendously important medicinal plant species.

Two New Dibenzylbutyrolactone Type Lignans from the Stems of Kadsura heteroclita

Two new lignans, named as 6-hydroxyhinokinin and 6-hydroxyhinokinin-6- O-β-D-glucopyranoside, together with five known compounds: elemol, oplodiol, catechin, β-sitosterol and daucosterol were isolated from Kadsura heteroclita. The structures of these compounds were characterized by extensive 1D and 2D NMR spectral experiments, chemical analysis and comparison with literature data. The absolute structures of the novel lignans were elucidated as 8 S, 8′ S, based on their optical rotations.

Triterpenoids and lignans from the stems of Schisandra glaucescens

Two new triterpenoids, 24( E)-3 α,12 α-dihydroxyl-lanost-9(11),24-dien-26-oid acid (1) and 3,4- seco-24( Z)-6 α,7 β-dihydroxyl-cycloart-4(28),24-dien-3,26-dioic-3-methyl ester (2), and ten known ones (3-12), together with eight lignans (13-20), were isolated from the stems of Schisandra glaucescens. Their structures were established on the basis of extensive spectroscopic analyses. Compounds 1-3, 5-7, 9, 11-13 and 15-18 were isolated from this species for the first time. 1 and 2 were evaluated for their in vitro cytotoxicities against the mouse cancer B16 cell line, human cancer HepG2 and MCF7 cell lines by MTT assay.

Triterpenes from Kadsura coccinea

In vitro anti-allergic screening of medicinal herbal extracts revealed that the 80% acetone extract of the rhizome of Kadsura coccinea inhibited nitric oxide (NO) production in a lipopolysaccharide (LPS) and recombinant mouse interferon-γ (IFN-γ) activated murine macrophage like cell line, RAW264.7. Further fractionation of the EtOAc extract led to the isolation of one new 3,4-seco-lanostane type triterpene named kadsuracoccin acid A (1) together with two known triterpenes anwuweizonic acid (2) and neokadsuranic acid B (3). Compounds 1−3 did not exhibit any inhibitory activities for NO production and IFN-γ activation.

Lanostane-type triterpenoids from the roots of Kadsura coccinea

Seven new lanostane-type triterpenoids, seco-coccinic acids A-F (1- 6) and coccinilactone A (7), were isolated from the roots of Kadsura coccinea. Their structures were established on the basis of spectroscopic data analysis. The absolute configuration at C-24 of compound 5 was confirmed by the modified Mosher's method. The cell growth inhibitory effects of these compounds were determined in human leukemia HL-60 cells, and it was found that compounds 1, 2, 3, and 5 exhibited antiproliferative effects with GI 50 values ranging from 6.8 to 42.1 microM.