Four New Limonoids from the Barks of Toona ciliata

Abstract

Four new limonoids, toonayunnanaes F − I (1 − 4), and six known compounds (5 − 10) were isolated from the barks of Toona ciliata. Their structures were elucidated by thoroughly analyzing of NMR and HRMS data, and single-crystal X-ray diffraction of 1. The oxetane ring moiety in 1 was rare in limonoids and other natural products. Compound 1 showed nitric oxide (NO) inhibitory effect with an IC50 38.45 ± 0.41 µM in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages. Graphic Abstract

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 ).…”

“…5), and others (A207-A223). 42,80,82,95,99,102,127,128,146,154 2.2.2 Ring-seco limonoids. Ring A-seco limonoids (B1-B70) were mainly distributed in the genera Toona, 101,103,[155][156][157] Munronia, 78,87,108,128,158 and Aphanamixis.…”

“…66,95,141,146,[323][324][325][326] The 29-norlimonoids, toonayunnanae I, ciliatasecones N, R, ciliatones F, L, toonamicronoids A, B, toonanoronoids A-H, ciliatonoid C, toonasinenine D, and toonaciliatins K, L, N, O (D14-D38) were entirely obtained from the genus of Toona. 80,100,103,156,[165][166][167]327,328 C-28 and C-29 were completely decarbonized in the structure of ceramicines K (D48) 323 and M (D49). 66 The unique 30-norlimonoids (D39-D43) were only discovered in T. connaroides, and were probably derived from andirobin.…”

Chemistry and Biology of Novel Meliaceae Limonoids

“…The epoxide ring in compound (151) is opened in Dysobinol (154). Compounds (155)(156)(157) are structurally similar to compound (151) but differ in substituents at B and C rings. Toonasinenoid E ( 158) is C16 hydroxy analogs of previously reported Trichilenone acetate 99 .…”