Tobacco Chemistry. 51. New Cembranic Diterpenoids from Greek Tobacco.

Behr, Dan; Wahlberg, Inger; Nishida, Toshiaki; Enzell, Curt R.; Berg, Jan-Erik; Pilotti, Anne‐Marie

doi:10.3891/acta.chem.scand.34b-0195

Cited by 25 publications

(34 citation statements)

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“…With the exception of (8'R)-cucurbitachrome 1 (9), where the sample amount was not sufficient for any "C-NMR (8) analysis, and cucurbitaxanthin B (6), where 13C-NMR data could be extracted only from traces of an inverse HMQC experiment and, as a consequence, no S(C) information of quaternary C-atoms were available, I3C-line assignments were successfully achieved by means of I3C, DEPT-135, and inverse HMQC experiments. The I3C-NMR data of the 3,6-epoxy-end group were identical with the data found for cucurbitaxanthin A (5) originating from pumpkin [6] and for 3,6-epoxy-7-megastigmene-5,9-diol originating from Greek tobacco [14], except the signals of C(2) and C(4) [6]. However, I3C,IH-shift-correlation experiments with cycloviolaxanthin (8) allowed the unambiguous assignment of C (2) to the I3C-signal at 48.53 ppm and of C(4) to that at 47.75 ppm (see Fig.…”

supporting

confidence: 66%

Reisolation of Carotenoid 3,6‐Epoxides from Red Paprika (Capsicum annuum)

Deli

Molnár

Matus

et al. 1996

Helvetica Chimica Acta

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Cucurbitaxanthin A (= (3S,5R,6R,3′R)‐3,6‐epoxy‐5,6‐dihydro‐β,β‐ carotene‐5,3′‐diol; 5), cucurbitaxanthin B (= (3S,5R,6R,3′S,5′R,6′S)‐3,6,5′, 6′‐diepoxy‐5,6,5′,6′‐tetrahydro‐β,β‐carotene‐5,3′‐diol; 6), the epimeric cucurbitachromes 1 and 2 (= (3S,5R,6R,3′S,5′R,8′S)‐ and (3S,5R,6R,3′S,5′R,8′R)‐3,6,5′, 8′‐diepoxy‐5,6,5′,6′‐tetrahydro‐β,β‐carotene‐5,3′‐diol, resp.; 9/10), cycloviolaxanthin (= (3S,5R,6R,3′S,5′R,6′R)‐3,6,3′, 6′‐diepoxy‐5,6,5′,6′‐tetrahydro‐β,κs‐carotene‐5,5′‐diol; 8), and capsanthin 3,6‐epoxide (= (3S,5R,6R,3′S,5′R)‐3,6‐epoxy‐5,6‐dihydro −5,3′‐dihydroxy‐β,κ‐caroten‐6′‐one; 7) were isolated from red spice paprika (Capsicum annuum var. longum) and characterized by their 1H‐ and 13C‐NMR, mass, and CD spectra.

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supporting

confidence: 66%

Reisolation of Carotenoid 3,6‐Epoxides from Red Paprika (Capsicum annuum)

Deli

Molnár

Matus

et al. 1996

Helvetica Chimica Acta

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“…Foliasalacioside L (8) C-NMR spectra were similar to those of 5,6-dihydro-5-hydroxy-3,6-epoxy-b-ionol, 48,49) except for the around of the 9-position. The position of the glycoside moiety in 8 was clarified on the basis of the HMBC experiment, which showed long-range correlation between the 1Ј-position and the 9-position.…”

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confidence: 62%

“…50,51) The carbon signal of the 9-position on 8 was observed at d 78.1, so that the configuration of the 9-position was determined to be R form. Finally, enzymatic hydrolysis of 8 gave an aglycon, 5,6-dihydro-5-hydroxy-3,6-epoxy-bionol (8a), 48,49) whose relative stereostructure was determined by X-ray analysis at its nitrobenzoyl derivative. Consequently, foliasalacioside L (8) was determined to be (3R*,5S*,6S*,7E,9R)-…”

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confidence: 99%

Chemical Structures and Hepatoprotective Effects of Constituents from the Leaves of Salacia chinensis

Nakamura

Zhang

Matsuda

et al. 2011

CHEMICAL & PHARMACEUTICAL BULLETIN

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In the course of our characterization studies on bioactive constituents from Salacia species (Hippocrateaceae), [1][2][3][4][5][6] we have reported the isolation and absolute stereostructure elucidation of 13 megastigmane glycosides, 7 phenolic glycosides, and 11 triterpenes from the leaves of Salacia chinensis collected in Thailand together with 40 known constituents. 7-11)As a continuning study on the leaves of Salacia chinensis, the methanolic (MeOH) extract was found to show a protective effect on D-galactosamine-induced cytotoxicity in primary cultured mouse hepatocytes. From the MeOH extract, eight new glycosides, named foliachinenosides E, F, G, H, and I, and foliasalaciosides J, K, and L, were isolated together with 26 known constituents. Furthermore, we examined the hepatoprotective effects of the isolated compounds on D-galactosamine-induced cytotoxicity. In this paper, we describe the isolation and structure elucidation of the new constituents (1-8) and the hepatoprotective effects of isolated compounds from the leaves of Salacia chinensis.The dried leaves of S. chinensis, which were collected at Nakhon Si Thammarat province, Thailand, were finely cut and extracted with MeOH to furnish a MeOH extract (13.0%). The MeOH extract was partitioned into an EtOAc-H 2 O (1 : 1, v/v) mixture to furnish an EtOAc-soluble fraction (4.1%) and an aqueous phase. The aqueous phase was further extracted with n-BuOH to give an n-BuOH-soluble fraction (2.4%) and a H 2 O-soluble fraction (6.6%). The n-BuOH-soluble fraction was subjected to Diaion HP-20 column chromatography (H 2 O→MeOH) to give the water-and MeOHeluted fractions as previously reported.7) The EtOAc-soluble fraction and the MeOH-eluted fraction were respectively subjected to normal-and reversed-phase silica gel column chromatographies, and finally HPLC to give eight new compounds, foliachinenosides E (1, 0.00009%), F (2, 0.00013%), G (3, 0.00017%), H (4, 0.00048%), and I (5, 0.0018%), and foliasalaciosides J (6, 0.00017%), K (7, 0.00016%), and L (8, 0.00007%), together with 26 known compounds, 3-methyl-2-but-2-en-1-ol 6-O-a-L-arabinopyranosyl-b-D-glucopyranoside (9, 0.0017%), 12) (3Z)-3-hexen-1-ol 6-O-a-L-arabinopyranosyl-b-D-glucopyranoside (10, 0.0014%), 13) 2,4,6-trimethoxyphenol 1-O-b-D-glucopyranoside (11, 0.00016%), 14) benzyl alcohol b-D-glucopyranoside (12, 0.00003%), 15) benzyl alco- Yamashina-ku, Kyoto 607-8412, Japan: and b Pharmaceutical Research and Technology Institute, Kinki University; 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. Received April 27, 2011; accepted May 26, 2011; published

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“…These spectral data led us to conclude that the aglycone structure of 1 is 3,6-epoxy-7-megastigmene-5,9-diol, which was isolated from tobacco. 8,9 Also, the sugar moiety appeared at δ H = 4.38 (1H, d, J = 7.5 Hz), 3.82 (1H, H COSY, and HMBC spectra revealed that 1 had the same planar structure as crotalionoside C isolated from Crotalaria zanzibarica, 11 except for the optical rotation value. The optical rotation of 1 ( : −13.0°) was almost of the same value but of opposite sign to that of crotalionoside C ( : +15.8°), which suggested that compound 1 could be a stereoisomer of crotalionoside C. The relative stereochemistry of the aglycone moiety was characterized by a NOESY experiment, which showed NOE correlations between the following proton pairs (H-2a/H-4a, and H-12; H-2b/H-4b, and H-11; H-11/H-7 and H-3) as shown in Figure 3.…”

mentioning

confidence: 99%