ABSTRACT
The structure of the title com-pound, C17H20O4 [systematic name: (1aS,3aR,4aS,5aR)-15-(acet-oxy)linden-7(11),8-trieno-12,8-lactone or (4aR,5S,5aR,6aS,6bR)-5-(acet-oxy-meth-yl)-4a,5,5a,6,6a,6b-hexa-hydro-3,6b-di-methyl-cyclo-propa[2,3]indeno-[5,6-b]furan-2(4H)-one, ent-chloranthalactone C], a natural product iso-lated from the whole plant Chloranthus japonicus Sieb., is a typical lin-den-ane-type sesquiterpenoid. The mol-ecule com-prises a bi-cyclo-[3.1.0]hexane ring (A/B system) bearing an acetoxymethyl (C-4) group, a bi-cyclo-[4.3.0]nonane ring (B/C system) containing a double bond (C-8/9) and a chiral quaternary carbon (C-10), and a 7(11)-en-12,8-olide structural moiety on the cyclo-hexan-8-ene (C ring). In the tetra-cyclic skeleton, the 1,3-cyclo-propane ring has a ß-con-figuration, and atoms H-5 and H3-14 have α- and ß-orientations, respectively. In the crystal, the mol-ecules are assembled into a two-dimensional network by weak Oâ¯H/Hâ¯O inter-actions. Hirshfeld surface analysis illustrates that the greatest contributions are from Hâ¯H (55.2%), Oâ¯H/Hâ¯O (34.6%) and Câ¯H/Hâ¯C (8.9%) contacts.
ABSTRACT
Two new sesquiterpenes, namely, 1ß,10ß-dihydroxy-eremophil-7(11), 8-dien-12,8-olide (1) and 8,12-epoxy-1ß-hydroxyeudesm-3,7,11-trien-9-one (2), together with three known sesquiterpenoids, shizukolidol (3), 4α-hydroxy-5α(H)-8ß-methoxy-eudesm-7(11)-en-12,8-olide (4), and neolitacumone B (5), and two known monoterpenes, (3R,4S,6R)-p-menth-1-en-3,6-diol (6) and (R)-p-menth-1-en-4,7-diol (7), were isolated from the whole plant of Chloranthus japonicus Sieb. Their structures were elucidated on the basis of spectroscopic data analysis and comparison with those of related known compounds. Compounds 4-7 were isolated from this plant for the first time.
Subject(s)
Magnoliopsida/chemistry , Sesquiterpenes/isolation & purification , Animals , Artemia/drug effects , Medicine, Chinese Traditional , Plant Extracts/analysis , Sesquiterpenes/chemistry , Sesquiterpenes/toxicityABSTRACT
The title compound [systematic name: [(1α,14α,16ß)-20-ethyl-8,9,10-trihy-droxy-1,14,16-tri-meth-oxy-aconitan-4-yl 2-amino-benzoate], C30H42N2O8, a natural C19-diterpenoid alkaloid, possesses an aconitane carbon skeleton with four six-membered rings and two five-membered rings. The fused ring system contains two chair, one boat, one twist-boat and two envelope conformations. Intra-molecular N-Hâ¯O hydrogen bonds are observed between the amino and carbonyl groups. The mol-ecules are linked together via O-Hâ¯O hydrogen bonds, forming a three-dimensional framework.
ABSTRACT
The title compound, C30H42N2O7 [systematic name: (1S,4S,5S,7S,8S,9S,10S,11S,13R,14S,16S,17R)-20-ethyl-4,8,9-trihy-droxy-1,14,16-tri-meth-oxy-aconitan-4-yl 2-amino-benzoate], isolated from roots of Aconitum sinomontanum Nakai, is a typical aconitane-type C19-diterpenoid alkaloid, which crystallizes with two independent mol-ecules in the asymmetric unit. The conformations of the two independent mol-ecules are closely similar. Each mol-ecule comprises four six-membered rings (A, B, D and E) including one six-membered N-containing heterocyclic ring (E), and two five-membered rings (C and F). Rings A, B and E adopt chair conformations, while ring D displays a boat conformation. Five-membered rings C and F exhibit envelope conformations. IntramolecularN-Hâ¯O hydrogen bonds between the amino group and carbonyl O atom help to stabilize molecular structure. In the crystal, O-Hâ¯O hydrogen bonds link the mol-ecules into zigzag chains propagating in [010].
