Three New Diterpenoids Based on the Novel Sarcopetalane Skeleton from Croton s arcopetalus (original) (raw)

Diterpenoids and Triterpenoids from Euphorbia retusa

Journal of Natural Products, 2009

Six new ent-abietane lactones (1-6), three new esterified tetracyclic triterpenes (7-9), and seven known diterpenoids and triterpenoids were isolated from the roots of Euphorbia retusa. Their structures were elucidated by means of spectroscopic studies including 1D and 2D NMR, mass spectrometry, chemical transformation, and comparison with literature data.

Ent-3,4-seco-labdane and ent-labdane diterpenoids from Croton stipuliformis (Euphorbiaceae)

Phytochemistry, 2008

From a methanolic extract of the leaves of Croton stipuliformis, three ent-3,4-seco-labdanes (1-3) and an ent-labdane (4) together with the known compounds 6-hydroxynidorellol (5), maravuic acid, and sitosterol were isolated and identified from their spectroscopic data. The absolute stereochemistry of compound 4 was determined by application of Mosher's method in the NMR tube.

Eight New Diterpenoids and Two New Nor-Diterpenoids from the Stems of Croton cascarilloides

Chemical and Pharmaceutical Bulletin, 2013

From the stems of Croton cascarilloides, eight new diterpenoids, named crotocascarins A-H (1-8), having a crotofolane skeleton were isolated along with two new nor-diterpenoids (9 and 10), named crotocascarins α and β, derived through rearrangement of the crotofolane skeleton. The structures of these compounds were elucidated by means of extensive one-and two-dimensional NMR spectroscopic analyses. The absolute structures of the diterpene moiety were determined by application of the circular dichroism (CD) rule for the γ-lactone ring. The relative structures of the two crotofolanes (1 and 2) and one rearranged compound (9) were confirmed by X-ray crystallographic analyses. Compounds 1, 2 and 9 possessed 2-methylbutyric acid in their molecules, the absolute configuration of which was found to be 2S by comparison of its HPLC behavior with that of an authentic sample. Therefore, the absolute structures of these crotocascarins (1, 2 and 9) were unambiguously determined. The absolute structures of crotofolanes are reported for the first time in this paper.

Abietane diterpenes from Sagittaria montevidensis ssp montevidensis Charm. & Schltdl

Journal of The Brazilian Chemical Society, 2007

Two new abietane-type diterpenes, 3b-hydroxy-9a, 13a-epidioxyabiet-8(14)-ene (1) and 3-oxo-9a,13a-epidioxyabiet-8(14)-ene (2), were isolated from the methanolic crude extract of the petioles of Sagittaria montevidensis ssp montevidensis (Alismataceae). The structures of 1 and 2 were determined on the basis of spectrometric analyses including HREIMS, IR as well as 1H and 13C 1 and 2D NMR.

Abietatrienes diterpenoids from Sagittaria montevidensis SSP Montevidensis

Química Nova, 2010

The antimicrobial properties of the hexane, hexane/EtOAc and methanol fractions of the fresh petioles of Sagittaria montevidensis ssp montevidensis (Alismataceae) were evaluated against fungi and Gram-negative and Gram-positive bacteria. A new abietatrienetype diterpenoid, 3β,7α-dihydroxi-abieta-8,11,13-triene and the known 3β-hydroxy-abieta-8,11,13-trien-7-one were isolated from the most active fraction tested and the structures of these compounds were elucidated by data including IR, EIMS, and 1D and 2D NMR spectra.

Terpenoids from Croton cajucara

Phytochemistry, 1998

Key Word Index-Croton cajucara; Euphorbiaceae; clerodane diterpenes; t-cajucarin B; sacacarin; acetyl aleuritolic acid.

Diterpenes from Different Fungal Sources and Their 13C-NMR Data

Terpenes and Terpenoids, 2018

Diterpenes are one of the classes of natural products with about 7000 structures. The basic skeleton of diterpene contains 20 carbon atoms. Microbes contain a large number of diterpenoid with many oxidized carbons and nitrogen atoms. To date, a number of secondary metabolites have been isolated from fungal sources, and some of these examples showed diverse structural features and interesting biological activities. These classes of compounds have attracted the interest of natural product scientist due to their potential biological activities. This chapter includes recently (2013-2018) isolated compounds from various fungal sources especially cythane, clerodanes, halimanes, abietane, and indoletype diterpenes. Biosynthetic pathway of plants and fungi diterpenes showed homology at initial steps but showed differences at latter steps. The biological activity and 13 C-NMR data of these recently isolated compounds have been discussed. These diterpenes exhibited potential nitric oxide, anticancer, antioxidant, and antitumor properties. The diterpenes are clerodane, labdane, and kaurane derivatives. A brief discussion on the 13 C-NMR chemical shifts of these diterpenes has been discussed at the end of each type.