Rubescins A, B and C: New Havanensin Type Limonoids from Root Bark of <i>Trichilia rubescens</i> (Meliaceae)

Unusual Vilasinin-Class Limonoids from Trichilia rubescens

“…The molecular formula of compound 6 (rubescin P) was elucidated as C 28 H 34 O 6 , based on HRFABMS. The 1D NMR data for 6 were related to those of rubescins C [5] and J [8], which are vilasinin-class limonoids with an acetate at C-11. The major difference was the chemical shift at C-7 (δ C 75.4) and the appearance of a proton at δ H 4.09, suggesting the presence of a hydroxy group at C-7 (Tables 3 and 4).…”

“…Vilasinin is a ring-intact limonoid characterized by a tetrahydrofuran ring adjacent to the A and B rings (Figure 1). Currently, only 18 vilasinin-class limonoids have been reported from the genus Trichilia, with 15 isolated from T. rubescens [5][6][7][8][9][10][11][12].…”

“…Vilasinin is a ring-intact limonoid characterized by a tetrahydrofuran ring adjacent to the A and B rings (Figure 1). Currently, only 18 vilasinin-class limonoids have been reported from the genus Trichilia, with 15 isolated from T. rubescens [5][6][7][8][9][10][11][12]. In this study, extensive phytochemical research on T. rubescens led to the identification of eight new vilasinin-class limonoids, including the unusually chlorinated rubescins K-M (1-3), the 2,3-epoxylated rubescin N (4), and rubescins O-R (5-8) (Figure 2), along with six known vilasinin-class limonoids, rubescin E (9) [6], rubescin F (10) [7], rubescin H (11) [7], rubescin I (12) [8], rubescin J (13) [8], and TS3 (14) [9], three sesquiterpenes, guaianediol [13], alismol [14], and eudesm-4(15)-ene-1β,6α-diol [15], as well as two sterols, β-sitosterol and stigmasterol [16] (Figure 3).…”

Research progress of meliaceous limonoids from 2011 to 2021

“…About 223 new ring-intact limonoids were discovered in the last decade, accounting for 14.0% of the total, second only to rearranged limonoids (Tables S1.1–S1.3†). According to previous studies, these limonoids can be divided into the azadirone-class ( A1–A58 ), 79–109 cedrelone-class ( A59–A99 ), 97,99,102,105,110–115 havanensin-class ( A100–A121 ), 97,98,108,116–130 trichilin-class ( A122–A168 ), 119,120,122,125,131–140 vilasinin-calss ( A169–A206 ) 82,87,122,128,132,141–153 (Fig. 5), and others ( A207–A223 ).…”

Protective Effect of Apple Polyphenols on H₂O₂-Induced Oxidative Stress Damage in Human Colon Adenocarcinoma Caco-2 Cells

“…[19][20][21][22] Hydrogen peroxide (H 2 O 2 ) which is an important ROS, could induce the oxidative stress damage and apoptosis of many cells. [23][24][25][26] Therefore, this study evaluated the protective effect of AP on the oxidative stress damage of Caco-2 cells induced by H 2 O 2 , in which cell viability, apoptosis, as well as oxidative stress parameters of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), catalase (CAT) and malondialdehyde (MDA) were explored. Chemical Characterization of AP Chemical constituents of AP were analyzed with an HPLC system (Shimadzu Scientific Instruments, Tokyo, Japan) equipped with a diode array detector (DAD).…”