Corymbulosins D–H, 2-Hydroxy- and 2-Oxo-clerodane Diterpenes from the Bark of <i>Laetia corymbulosa</i>

Suzuki, Airi; Saito, Yohei; Fukuyoshi, Shuichi; Goto, Masuo; Miyake, Katsunori; Newman, David J.; O’Keefe, Barry R.; Lee, Kuo Hsiung̀; Nakagawa‐Goto, Kyoko

doi:10.1021/acs.jnatprod.6b01151

Cited by 10 publications

(21 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Taking into consideration the six units of unsaturation that were confirmed in 1 (two acetoxy groups, a propionate group, and three double bonds), as well as 13 C NMR-derived evidence for the presence of a keto carbonyl (δ C 207.9, C-6), it was concluded that the remaining three units of unsaturation could be accounted for as three rings. Bearing this in mind, an analysis of the 1 H– 1 H COSY and HMBC correlation data (Figure ) led to the proposal that 1 featured a tricyclic clerodane diterpene core. − More specifically, compound 1 belongs to a subgroup of clerodane diterpenes that possess an isozuelanin skeleton . However, in contrast to the reported isozuelanin-containing natural products that bear a methylene, a hydroxy, or an alkoxy group at C-6, metabolite 1 is the first member of this class to feature a C-6 keto carbonyl group …”

Section: Resultssupporting

confidence: 87%

Anacolosins A–F and Corymbulosins X and Y, Clerodane Diterpenes from Anacolosa clarkii Exhibiting Cytotoxicity toward Pediatric Cancer Cell Lines

et al. 2019

Self Cite

View full text Add to dashboard Cite

An extract of the plant Anacolosa clarkii was obtained from the NCI Natural Products Repository, and it showed cytotoxic activity toward several types of pediatric solid tumor cell lines. Bioassay-guided fractionation led to the purification of eight new clerodane diterpenes [anacolosins A−F (1−6) and corymbulosins X and Y (7 and 8)] and two known compounds (9 and 10) that contained an isozuelanin skeleton. The structures of the new natural products were determined using 1D and 2D NMR and HRESIMS data, while the relative and absolute configurations of the compounds were assessed using a combination of 1 H NMR coupling constant data, ROESY experiments, ECD (electronic circular dichroism) and VCD (vibrational circular dichroism) spectroscopy, chemical methods (including Mosher and 2-naphthacyl esterification), and chiral HPLC analyses. The purified natural products exhibited a range of cytotoxic activities against cell lines representing four pediatric cancer types (i.e., rhabdomyosarcoma, Ewing sarcoma, medulloblastoma, and hepatoblastoma) with total growth inhibitory (TGI) values in the range 0.2−4.1 μM. The rhabdomyosarcoma and medulloblastoma cell lines showed higher sensitivity to compounds 1−4, which are the first compounds reported to contain an isozuelanin skeleton and feature keto carbonyl groups at the C-6 positions. In contrast, the hepatoblastoma cell line was modestly more sensitive to 7−10, which contained a C-6 hydroxy group moiety.

show abstract

Section: Resultssupporting

confidence: 87%

Anacolosins A–F and Corymbulosins X and Y, Clerodane Diterpenes from Anacolosa clarkii Exhibiting Cytotoxicity toward Pediatric Cancer Cell Lines

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…C. laevigata , which is called the glossy laurel or red-fruited laurel, are distributed in rainforest areas, mainly in eastern Australia. Only two phytochemical researches of this species have been reported so far. , In our continuous investigation of rainforest plants, ,, we performed a phytochemical study on a 50% MeOH/CH 2 Cl 2 extract (N025439) of the leaves and twigs of C. laevigata . In this study, six new δ-lactone derivatives, named cryptolaevilactones A–F ( 1 – 6 ; Figure ), were isolated from the EtOAc-soluble portion of the extract.…”

mentioning

confidence: 99%

Secondary Metabolites, Monoterpene–Polyketides Containing a Spiro[3.5]nonane from Cryptocarya laevigata

et al. 2018

Self Cite

View full text Add to dashboard Cite

Six novel lactone derivatives, cryptolaevilactones A-F (1-6), were isolated from Cryptocarya laevigata. Their unique spiro[3.5]nonane moiety by hetero [2 + 2] cyclization with monoterpene and polyketide was found for the first time in nature. Structural elucidation using various nuclear magnetic resonance (NMR) techniques revealed that 1-3 and 4-6 are diastereomers and partially established the absolute configurations.

show abstract

“…All isolates were evaluated for antiproliferative activity against five human cancer cell lines, A-549, MDA-MB-231, KB, KB-VIN, and MCF-7, using the sulforhodamine B (SRB) method with vincristine (VIN) and paclitaxel (PXL) as positive controls . All of the compounds, except 2 and 14 , exhibited antiproliferative activity (IC 50 2.6–8.3 μM) against multidrug-resistant KB subline KB-VIN (Table ).…”

Section: Resultsmentioning

confidence: 99%

Taburnaemines A–I, Cytotoxic Vobasinyl-Iboga-Type Bisindole Alkaloids from Tabernaemontana corymbosa

et al. 2018

Self Cite

View full text Add to dashboard Cite

Nineteen vobasinyl-ibogan-type bisindole alkaloids, including nine new compounds, taburnaemines A-I (1-9), were isolated from the twigs and leaves of Tabernaemontana corymbosa. The structures and absolute configurations of the new alkaloids were determined by a combination of MS, NMR, and ECD analyses. Alkaloids 1-5 contain a rare 1,3-oxazinane moiety in the vobasinyl unit, while 6 has an uncommon 1,3-oxazolidine moiety in the iboga unit. The absolute configurations of alkaloid 1 and the known alkaloid tabernaecorymbosine A (10) were confirmed by single-crystal X-ray diffraction analysis. All of the bisindole alkaloids, except 2 and 16'-decarbomethoxytabernaecorymbosine A (14), showed antiproliferative activity (IC 2.6-9.8 μM) against several human cancer cell lines, including A-549, MDA-MB-231, MCF-7, KB, and P-glycoprotein-overexpressing multidrug-resistant KB cells. The preliminary structure-activity relationship correlations are also discussed.

show abstract

Corymbulosins D–H, 2-Hydroxy- and 2-Oxo-clerodane Diterpenes from the Bark of Laetia corymbulosa

Cited by 10 publications

References 10 publications

Anacolosins A–F and Corymbulosins X and Y, Clerodane Diterpenes from Anacolosa clarkii Exhibiting Cytotoxicity toward Pediatric Cancer Cell Lines

Anacolosins A–F and Corymbulosins X and Y, Clerodane Diterpenes from Anacolosa clarkii Exhibiting Cytotoxicity toward Pediatric Cancer Cell Lines

Secondary Metabolites, Monoterpene–Polyketides Containing a Spiro[3.5]nonane from Cryptocarya laevigata

Taburnaemines A–I, Cytotoxic Vobasinyl-Iboga-Type Bisindole Alkaloids from Tabernaemontana corymbosa

Contact Info

Product

Resources

About