Ent-abietane and ent-pimarane diterpenoids from Croton mubango (Euphorbiaceae)

Sani M Isyaka; Moses K Langat; Eduard Mas-Claret; Blaise M Mbala; Bienvenu K Mvingu; Dulcie A Mulholland

doi:10.1016/j.phytochem.2019.112217

Ent-abietane and ent-pimarane diterpenoids from Croton mubango (Euphorbiaceae)

Phytochemistry. 2020 Feb:170:112217. doi: 10.1016/j.phytochem.2019.112217. Epub 2019 Dec 4.

Authors

Sani M Isyaka¹, Moses K Langat², Eduard Mas-Claret¹, Blaise M Mbala³, Bienvenu K Mvingu³, Dulcie A Mulholland⁴

Affiliations

¹ Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK.
² Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK; Jodrell Laboratory, Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3DS, United Kingdom; School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa.
³ Departement de Chimie et Industry, Faculte des Sciences, Universite de Kinshasa, B.P.190 Kin XI, Congo.
⁴ Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK; School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa. Electronic address: d.mulholland@surrey.ac.uk.

PMID: 31812109
DOI: 10.1016/j.phytochem.2019.112217

Abstract

Twelve ent-abietane and two ent-pimarane diterpenoids were isolated from the leaves of Croton mubango Müll. Arg. (Euphorbiaceae) collected in the Democratic Republic of the Congo. 2β-Hydroxy-ent-abieta-7,13-dien-3-one, 15-hydroxy-ent-abieta-7,13-dien-3-one, 13α,15-dihydroxy-ent-abieta-8(14)-en-3-one, 2β,9,13-trihydroxy-ent-abieta-7-en-3-one, 2β,7β-dihydroxy-ent-abieta-8,11,13-trien-3-one, 15-hydroxy-ent-abieta-8,11,13-trien-3-one and ent-pimara-8(14),15-dien-3-one and the ent-forms of the previously reported normal series diterpenoids, ent-abieta-8,11,13-trien-3-one, 7β-hydroxy-ent-abieta-8,11,13-trien-3-one, 3α-hydroxy-ent-abieta-8,11,13-triene, 15-hydroxy-ent-abieta-8,11,13-triene and 6β-hydroxy-ent-abieta-8,11,13-triene are reported here for the first time. Structures were established using HRESIMS, FTIR, NMR, DP4+ probability calculations and by comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. Ent-pimara-8(14), 15-dien-3-one, showed antiproliferative activity against melanoma (MALME-3M), renal (UO-31) and ovarian cancer cell lines (IGROV1) at a concentration of 10^-5 M in the NCI 60 screen.

Keywords: Croton mubango; Cytotoxicity screening; DP4+ calculations; Ent-abietane; Ent-pimarane; Euphorbiaceae.

MeSH terms

Antineoplastic Agents, Phytogenic / chemistry
Antineoplastic Agents, Phytogenic / isolation & purification
Antineoplastic Agents, Phytogenic / pharmacology*
Cell Line, Tumor
Cell Proliferation / drug effects
Diterpenes / chemistry
Diterpenes / isolation & purification
Diterpenes / pharmacology*
Dose-Response Relationship, Drug
Drug Screening Assays, Antitumor
Euphorbiaceae / chemistry*
Humans
Molecular Conformation
Phytochemicals / chemistry
Phytochemicals / isolation & purification
Phytochemicals / pharmacology*
Structure-Activity Relationship

Substances

Antineoplastic Agents, Phytogenic
Diterpenes
Phytochemicals