Coumarin and terpenoids from Perezia alamani var. oolepis

Joseph‐Nathan, Pedro; Hernández, José Falcón; Román, Luisa U.; García, E.; Mendoza, V.; Mendoza, Sandra

doi:10.1016/s0031-9422(00)82430-9

Cited by 48 publications

(23 citation statements)

References 10 publications

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“…The molecular formula of 1 was determined as C 17 13 C NMR data for the coumarin moiety were very similar to those described for 8-hydroxypereflorine (5), 6 isolated from Perezia alamani, except for the C-5 signal, which is shifted 2.8 ppm to lower field when the glucosyl group replaces the hydroxyl group. Such a shift is in agreement with that described for other coumarins.…”

Section: Resultsmentioning

confidence: 56%

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A new coumarin from Perezia hebeclada

Hernández-Carlos

Burgueño‐Tapia

Joseph‐Nathan

2003

Magnetic Reson in Chemistry

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Section: Resultsmentioning

confidence: 56%

“…NMR measurements were carried out using 5 mm probes at 22°C from CDCl 3 and DMSO-d 6 solutions with TMS as the internal standard. Typical 1D 1 H and 13 C spectra were acquired under standard conditions on Varian Mercury spectrometers operated at 300 and 75.4 MHz, respectively.…”

Section: Nmr Spectroscopymentioning

confidence: 99%

A new coumarin from Perezia hebeclada

Hernández-Carlos

Burgueño‐Tapia

Joseph‐Nathan

2003

Magnetic Reson in Chemistry

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“…Perezone (1), hydroxyperezone (2), O-acetylperezone sulfide (11), isoperezone (12) and perezone sulfide (14) were available from previous studies. 11,14 Diperezone (13) was prepared by treating perezone with BF 3 ÐOEt 2 as described.…”

Section: Compoundsmentioning

confidence: 99%

13C NMR substituent chemical shifts in hydroxy-p-benzoquinones

Burgueño‐Tapia

Joseph‐Nathan

2000

Magn. Reson. Chem.

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“…The UV spectrum also suggested the presence of an a,b-unsaturated ketone (l max ϭ237 nm). The 1 H- (Table 1) and 13 C-NMR spectra ( H COSY spectrum of 1 implied connectivities for H 2 -2-H-3, H-3-H-7, H-7-H-8, H-8-H-9, and H-9-H 3 -10. Interpretation of the HMBC spectrum revealed correlations from H 2 -2 to C-1 and C-4; H-5 to C-3 and C-7; H-7 to C-6; CH 3 O-1 to C-1; and CH 3 O-6 to C-6.…”

mentioning

confidence: 98%

“…In conclusion, we described here the isolation and structure elucidation of erigerenones A (1), B (2), and C (3) from the aerial parts of E. annuus, E. philadelphicus, and E. sumatrensis. Although dibenzocyclooctadienone lignans such as steganone 12) and benzocyclooctadienone sesquiterpenes such as isoparvifolinone 13) are known, compound 3 is, to the best of our knowledge, the first example of a naturally occurring cyclooctadienone derivative without the fused phenyl system.…”

mentioning

confidence: 99%

Two New Cyclopentenone Derivatives and a New Cyclooctadienone Derivative from Erigeron annuus (L.) PERS., Erigeron philadelphicus L., and Erigeron sumatrensis RETZ.

Iijima

Yaoita

Kikuchi

2003

CHEMICAL & PHARMACEUTICAL BULLETIN

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The genus Erigeron is a common group of Compositae plants, and Erigeron annuus (L.) PERS. (himejyon in Japanese), Erigeron philadelphicus L. (harujion in Japanese) and Erigeron sumatrensis RETZ. (oarechinogiku in Japanese) are now, as naturalized weeds, widely distributed throughout urban and rural areas of Japan.1) Among these, E. annuus has been used as an hypoglycemic drug in China.2) The constituents of E. annuus, E. philadelphicus, and E. sumatrensis have been previously investigated and shown to contain monoterpenoids, 3) sesquiterpenoids, 3) diterpenoid, 4) polyacetylenic compounds, 5) and g-pyrone derivatives. 1) Recently we reported the isolation and structural elucidation of norisoprenoids, 6) sesquiterpenoids, 7) diterpenoids, 7) triterpenoids, 8) and sterols 8) from the aerial parts and roots of E. annuus, E. philadelphicus, and E. sumatrensis. As part of our continuing study of the constituents of the genus Erigeron plants, we now report the isolation and structural elucidation of two new cyclopentenone derivatives, erigerenons A (1) and B (2), and a new cyclooctadienone derivative, erigerenone C (3), from the aerial parts of E. annuus, E. philadelphicus, and E. sumatrensis.Compound 1 was isolated as a colorless oil, [a] D ϩ7.3°. The molecular formula was determined to be C 12 H 16 O 4 by high-resolution (HR)-electron ionization (EI)-MS. The IR spectrum showed the presence of ester (1735 cm Ϫ1) and a,bunsaturated ketone (1691, 1596 cm Ϫ1 ) functionalities. The UV spectrum also suggested the presence of an a,b-unsaturated ketone (l max ϭ237 nm). The 1 H- (Table 1) and 13 C-NMR spectra ( H COSY spectrum of 1 implied connectivities for H 2 -2-H-3, H-3-H-7, H-7-H-8, H-8-H-9, and H-9-H 3 -10. Interpretation of the HMBC spectrum revealed correlations from H 2 -2 to C-1 and C-4; H-5 to C-3 and C-7; H-7 to C-6; CH 3 O-1 to C-1; and CH 3 O-6 to C-6. Thus the gross structure of 1 was deduced to be as shown in Fig. 1. The relative stereochemistry at C-3 and C-7 was established by comparing the proton coupling constant between H-3 and H-7 with analogous couplings observed for other cyclopentenones.9,10) In cyclopentene rings, a vicinal coupling constant of 5-6 Hz normally indicates a cis relationship, while a coupling constant of ca. 2 Hz suggests a trans relationship.11) These observations have been extended to cyclopentenone rings and a similar correlation has been observed.9,10) Thus, in the case of 1, the small coupling constant of 2.2 Hz is suggestive of a trans relationship between H-3 and H-7. The geometry of the D 8 -double bond was deduced to be Z from 1 H-1 H coupling constant (Jϭ11.0 Hz) between H-8 and H-9. On the basis of the above data, the structure of 1 was represented as shown in the formula.Compound 2 Aoba-ku, Sendai, Miyagi 981-8558, Japan. Received March 6, 2003; accepted March 30, 2003 Two new cyclopentenone derivatives, erigerenones A (1) and B (2), and a new cyclooctadienone derivative, erigerenone C (3), were isolated from the aerial parts of Erigeron philadelphicus L. Compound 2 ...

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Coumarin and terpenoids from Perezia alamani var. oolepis

Cited by 48 publications

References 10 publications

A new coumarin from Perezia hebeclada

A new coumarin from Perezia hebeclada

13C NMR substituent chemical shifts in hydroxy-p-benzoquinones

Two New Cyclopentenone Derivatives and a New Cyclooctadienone Derivative from Erigeron annuus (L.) PERS., Erigeron philadelphicus L., and Erigeron sumatrensis RETZ.

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