Furanoditerpenoid lactones from the seeds of Caesalpinia minax Hance

Bioactive Compounds from Medicinal Plants in Myanmar

Myanmar is a country with rich natural resources and of these, medicinal plants play a vital role in the primary health care of its population. The people of Myanmar have used their own system of traditional medicine inclusive of the use of medicinal plants for 2000 years. However, systematic and scientific studies have only recently begun to be reported. Researchers from Japan, Germany, and Korea have collaborated with researchers in Myanmar on medicinal plants since 2000. During the past two decades, over 50 publications have been published in peer-reviewed journals. Altogether, 433 phytoconstituents, including 147 new and 286 known compounds from 26 plant species consisting of 29 samples native to Myanmar, have been collated. In this contribution, phytochemical and biological investigations of these plants, including information on traditional knowledge are compiled and discussed.

Caesalminaxins A-L, cassane diterpenoids from the seeds of Caesalpinia minax

Fourteen new cassane diterpenoids, caesalminaxins A-L (1-14), and three known compounds were isolated from the seeds of Caesalpinia minax. Among the new diterpenoids, compounds 3 and 4 possess a rare spiro C/D ring system. The C-16 epimeric mixture 1/2 has an unprecedented carbon skeleton, presumably derived from 3 by cleavage of the C-13-C-14 bond. Compound 5 is the first example of a cassane diterpenoid with a spiro A/B ring system. The structures of the compounds were elucidated on the basis of 1D and 2D NMR analysis, and the absolute configurations of 3, 4, 9, and 11 were determined by single-crystal X-ray crystallography. Biosynthesis pathways for 1/2, 3, and 5 are postulated. Compounds 4, 8, and the known bonducellpin D exhibited moderate activity against four tested human cancer cell lines, HepG-2, K562, HeLa, and Du145.

The genus Caesalpinia L. (Caesalpiniaceae): phytochemical and pharmacological characteristics

The genus Caesalpinia (Caesalpiniaceae) has more than 500 species, many of which have not yet been investigated for potential pharmacological activity. Several classes of chemical compounds, such as flavonoids, diterpenes, and steroids, have been isolated from various species of the genus Caesalpinia. It has been reported in the literature that these species exhibit a wide range of pharmacological properties, including antiulcer, anticancer, antidiabetic, anti-inflammatory, antimicrobial, and antirheumatic activities that have proven to be efficacious in ethnomedicinal practices. In this review we present chemical and pharmacological data from recent phytochemical studies on various plants of the genus Caesalpinia.

Cassane furanoditerpenoids from the seed kernels of Caesalpinia bonduc from Thailand

Three new cassane furanoditerpenoids ( 1- 3), together with 13 known cassane diterpenes ( 4- 16), were isolated from the EtOAc extract of the seed kernels of Caesalpinia bonduc. Their structures were elucidated on the basis of spectroscopic analysis, mainly NMR and MS. Compounds 1- 3 exhibited good antimalarial activity against the multidrug-resistant K1 strain of Plasmodium falciparum, while compound 4 was inactive. None of the compounds were cytotoxic against any of the tumor cell lines tested.

Cassane Diterpene-lactones from the Seed ofCaesalpinia minaxHance

Five new neocaesalpins, named neocaesalpin J-N (1-5, resp.), along with the known neocaesalpin A and eight known furanditerpenoids, namely epsilon-caesalpin, 7-acetoxy-epsilon-caesalpin, 14-deoxy-epsilon-caesalpin, caesalmins D-F, and bonducellins C and D, were isolated from the seeds of Caesalpinia minax HANCE. Their structures were determined on the basis of spectroscopic analyses.

Caesaldecan, a cassane diterpenoid from the leaves of Caesalpinia decapetala

A new cassane diterpenoid, caesaldecan, was isolated from Caesalpinia decapetala with eight known compounds, spathulenol, 4,5-epoxy-8(14)-caryophyllene, squalene, lupeol, trans-resveratrol, quercetin, astragalin, and stigmasterol. The (1)H- and (13)C-NMR spectra of the new compound were completely assigned by using a combination of 2D NMR techniques, namely, (1)H-(1)H COSY, HMQC, HMBC, and ROESY.

Molecular structures and antiviral activities of naturally occurring and modified cassane furanoditerpenoids and friedelane triterpenoids from Caesalpinia minax

Further investigation of the active components of the chloroform fraction of the seeds of Caesalpinia minax led to the isolation of a new cassane furanoditerpenoid, caesalmin H (1), together with two known furanoditerpenoid lactones, caesalmin B (2) and bonducellpin D (3). Reduction of the naturally abundant caesalmin D (9), E (10) and F (11) resulted in three new furanoditerpenoid derivatives 4-6. Phytochemical study of the stem of the same plant and subsequent reduction afforded two friedelane triterpenoids (7-8), which were identified by spectroscopic methods. Compounds 1-2 and 4-8 were corroborated by single crystal X-ray analysis. The factors governing the reduction of cassane furanoditerpenoids and friedelane triterpenoids were investigated by correlating the crystallographic results with density functional theory. The inhibitory activities of 2-8 on the Para3 virus were evaluated by cytopathogenic effects (CPE) reduction assay.

New antiviral cassane furanoditerpenes from Caesalpinia minax

A bioassay-guided study led to the isolation of five new cassane furanoditerpenes, designated as caesalmin C (1), D (2), E (3), F (4), and G (5), along with stigmasterol (6) from the seeds of Caesalpinia minax. The (1)H and (13)C NMR spectra were completely assigned by using a combination of 2D NMR analyses. The structures of all five furanoditerpenes were confirmed by X-ray analyses. The structure of 6 was verified by X-ray analysis for the first time. The bioassay results showed that the anti-Para3 virus activity of tetracyclic furanoditerpenoids 1-4 is more potent than that of the furanoditerpenoid lactone 5, which is in turn better than 6. As the major components of the plant possess significant potent activity, it may be feasible to develop new antiviral agents from this source.