Tetranortriterpenoids and related substances. Part 20. New tetranortriterpenoids from the seeds of Chukrasia tabularis(Meliaceae); simple esters of phragmalin and 12α-acetoxyphragmalin

Limonoids, Alkaloids, and a Coumarin from the Root and Stem Barks of Tetradium glabrifolium

“…Limonoids with oxidized furan rings are relatively rare in the Rutaceae (11), and it has been suggested that they are artifacts caused by air oxidation (12).…”

New Phragmalin-Type Limonoids from Chukrasia tabularis and Their α-Glucosidase Inhibitory Activity

“…Additionally, its root bark has been used for a long time as a traditional medicine for dispelling wind and heat from the body by the peoples in the tropical areas of Asia [2]. Previous phytochemical studies have reported a number of phragmalin-type limonoids from this plant [3], such as normal phragmalins and their orthoesters, 13/14/18-cyclopropanyl phragmalin-type orthoesters, C(15)-acyl phragmalins, 16-dinorphragmalins, C(15)-acyl 16-dinorphragmalins, 19-dinorphragmalins, and 16,19-dinorphragmalins [4,5,6,7,8,9,10,11,12,13,14,15], and their interesting biological properties including insecticidal, cytotoxic, anti-inflammatory, and delaying of rectifier ( I k ) k + current [16,17,18,19,20,21].…”

Chukfuransins A–D, Four New Phragmalin Limonoids with β-Furan Ring Involved in Skeleton Reconstruction from Chukrasia tabularis

“…velutina , is a primary source of phragmalin limonoids with nearly 140 possessing miscellaneous skeletons having been reported. Except the common phragmalin limonoids from which they were derived, dominant skeleton types including 16-nor type, 15 enolic acyl 16-nor type, 13/14/18 cyclopropanyl type, and 15-enolic acyl type were all biogenetically formed by alterations confined to D rings compared to the common type. In addition, tabuvelutin A and chukrasone B were the only two cases with C-19 degraded.…”

“…It is proposed that compounds 1 and 2 were biogenetically formed via a Michael addition mechanism involving a meliacin butenolide intermediate, a type of limonoid reported in C. tabularis , and a few other Meliaceae species such as Trichilia estipulata . A plausible biogenetic pathway of 1 and 2 was illustrated in Supporting Information Scheme 1.…”