Two new compounds fromKhaya senegalensis

Abstract

Two new compounds, khayseneganin I (1) and 2α,3α,16β-trihydroxy-20-acetoxy-20(R)-pregnane (2), along with six known compounds, 2α,3α,20-trihydroxy-16β-acetoxy-20(R)-pregnane (3), 2α,3β-dihydroxypregnan-16-one-2β,19-hemiketal (4), (+)-catechin (5), ivorenolide A (6), luteolin-7-O-α-l-rhamnoside (7), and ( - )-5'-methoxy-isolariciresinol-2a-O-β-d-xylopyranoside (8), were isolated from the leaves and twigs of Khaya senegalensis. The structures of new compounds were elucidated by 2D NMR spectroscopy and MS. Selected compounds (2-8) were evaluated for their antimicrobial activities and compounds 5 and 7 showed weak antimicrobial activities against MRSA 92(#) and MRSA 98(#).

Bioactivities of Steroids and Sesquiterpenes from the Branches and Leaves of Aglaia lawii

“…The 1 H and 13 C NMR data ( Table 1 and Table 2 ) of 1 displayed the characteristic resonances of four methyls ( δ H 2.01 (s), 1.42 (d, J = 6.3 Hz), 1.02 (s), and 0.79 (s), each 3H; δ C 21.6, 20.4, 19.5, and 13.5), seven sp 3 methylenes, a olefinic methine ( δ H 5.34, δ C 120.9), six sp 3 methines, including two oxymethines ( δ H 3.52, 5.06, δ C 71.7, 69.4), five quaternary carbons, including one ester carbonyl ( δ C 170.1) and a keto group ( δ C 215.5), which are characteristic signals for C21 steroid. Further careful analysis of the nuclear magnetic resonance (NMR) data indicated the structure of 1 was similar to that of 5,6-dehydrotoosendanesterol A [ 7 ]. The obvious differences were the presence of an acetyl group ( δ C 21.6, 170.1) in 1 instead of a methyl group in 5,6-dehydrotoosendanesterol A.…”

Limonoids from the Stem Bark of <i>Khaya senegalensis</i>

“…The structures of known compounds were identified as khayanolide B (7), 14) 1-O-deacetyl-2α-hydroxykhayanolide E (8), 16) 1-O-deacetylkhayanolide E (9), 14) senegalensions A (10), 11) khaysenegain E (11), 12) khaysenegain I (12) 17) by comparison of their physical and spectroscopic data with those of literatures.…”

Research progress of meliaceous limonoids from 2011 to 2021

“…The rest, about a quarter of phragmalins, are isolated from 10 genera. 53,86,162,183–185,191,199,206,213,236–238,240,251,256,260,266,303–311 The fragment of the ortho ester is one of the characteristics of phragmalin-class limonoids and only exists in phragmalins. Four classes of phragmalin orthoesters, 8,9,30-( C360–C399 ), 8,9,14-( C400 , C445–C448 ), 8,9,11-( C401–C403 , C420–C425 ), and 1,8,9-( C477–C599 ), have been summarized in previous reviews.…”