Caesalpins A–H, Bioactive Cassane-Type Diterpenes from the Seeds of Caesalpinia minax

Abstract

Eight new cassane-type diterpenes, caesalpins A-H (1-8), were isolated from the ethyl acetate extract of Caesalpinia minax. Compound 1 displayed significant antiproliferative activity against HepG-2 (IC50 4.7 μM) and MCF-7 (IC50 2.1 μM) cells, and compounds 2 and 4 exhibited selective cytotoxic activities against MCF-7 (IC50 7.9 μM) and AGS (IC50 6.5 μM) cells.

New Cassane-Type Diterpenoids from <i>Caesalpinia bonduc</i>

“…Caesall I (2) is, therefore, the 1-keto analogue of 1 and a perspective view of the molecular structure is presented in Fig. 1 C-NMR data were similar to caesalpin G, 8) except for the absence of one hydroxyl group, the presence of two acetoxy groups and the difference of the relative configuration at C-12. Three acetoxy groups were attached at C-1, C-2, C-3 respectively, on the basis of the HMBC correlations from H-1 (δ H (Fig.…”

“…Previous phytochemical investigations on plants of Caesalpinia have resulted in the isolation of several cassane and norcassane furanoditerpenes, [6][7][8][9] and seven new compounds, caesalls A-G, 10) were isolated in our previous research on C. bonduc. As a continuation of our study on this plant, the ethanol (95%) extract of the seed kernel was investigated.…”

“…The CD spectrum of 3 displayed a positive Cotton effect at 260 nm and a positive Cotton effect at 219 nm, confirming the (8R, 12S) absolute configuration for 3 based on the exciton chirality method and the γ-lactone rules. 8,[11][12][13] Thus, the structure of 3 was established as1α,2α,3α-triacetoxy-5α-hydroxy-12β-methoxycassa-14(17),13 (15) 6.01/6.02) with C-15 (δ C 37.4), C-12 (δ C 156.0), and C-13 (δ C 122.2). The HMBC correlations (Fig.…”

New Cassane Diterpenoids from <em>Caesalpinia sappan</em> and Their Antiplasmodial Activity

“…The HRESIMS spectrum demonstrated a quasi-molecular ion at m/z 454.2199 (Calcd for C24H33NO6Na, 454.2206), which in connection with the NMR data, confirmed that the molecular formula was C24H33NO6. The IR and UV spectra revealed absorptions for an amidogen (3190 cm −1 ), a carbonyl (1735 cm −1 ), and an α,β-unsaturated butenolide unit (210 nm; 1749 cm −1 ) [2]. The 1 H and 13 C APT NMR spectra (Table 1) displayed the olefinic proton signal at δH 5.86 (H-15, s) and four downfield-shifted carbon signals at δC 107.4 (C-12), 171.0 (C-13), 115.9 (C-15), and 179.9 (C-16), which also confirmed the presence of the α,β-unsaturated butenolide ring.…”

“…Previous phytochemical investigations indicated that this genus contains an abundant source of cassane diterpenes with different structure types, and most of them showed in vitro or in vivo pharmacological impacts such as antiproliferative [1][2][3], antiplasmodial [4][5], antibacterial [6], antihelmintic, and antineoplastic activity [7]. As a continuation of our project towards new bioactive diterpenes discovery from the genus Caesalpinia [2][3]8], we examined the chemical constituents of C. sappan and obtained two new cassane diterpenes, designated caesalsappanin R (1) and caesalsappanin S (2) (Figure 1). Compound 1 is a rather unusual cassane diterpenoid lactone-type skeleton, consisting of an N bridge between C-19 and C-20.…”