Biochemical Systematics and Ecology 29 (2001) 215}217
Totarol, totaradiol and ferruginol: three
diterpenes from
¹
huja plicata
(Cupressaceae)
Hazel Sharp
!
, Zahid Latif
!
, Barbara Bartholomew
!
,
Colin Bright
!
, Chris D. Jones
"
, Satyajit D. Sarker
#,
*
,
Robert J. Nash
$
!MolecularNature Limited, IGER, Plas Gogerddan, Aberystwyth, Ceredigion SY23 3EB, UK
"Forest Research, Cefn Gethiniog, Talybont-on-Usk, Brecon, Powys LD3 7YN, Wales, UK
#Pharmaceutical Sciences Section, School of Pharmacy, The Robert Gordon University, Schoolhill, Aberdeen AB10 1FR, Scotland, UK
$Institute of Grassland and Environmental Research, Plas Gogerddan, Aberystwyth, Ceredigion SY23 3EB, UK
Received 24 February 2000; accepted 26 April 2000
Keywords: ¹huja plicata; Cupressaceae; Totarol; Totaradiol; Ferruginol; Yatein; Vomifoliol; Chemotaxon-omy
1. Subject and source
Thuja plicata Donn ex D. Don (Family: Cupressaceae), commonly known as
`western red-cedarais an ornamental plant from North America, widely distributed in Alberta and British Columbia of Canada, and Alaska, California, Idaho, Montana, Oregon and Washington of the USA (USDA-ARS GRIN database, 2000). Plant material was collected during May 1998 from Beddgelert Forest plots in north Wales and a voucher specimen (IG147) for this collection has been retained at the herbarium of the Institute of Grassland and Environmental Research (IGER), Aberystwyth, Wales, UK
*Corresponding author. Tel.:#44-1224-262547; fax:#44-1224-262555.
E-mail address:s.sarker@rgu.ac.uk (S.D. Sarker).
2. Previous work
Not less than 30 di!erent plant secondary metabolites, notably, tropolones, ter-penoids, #avonoids, and lignans have previously been reported from T. plicata (Dictionary of Natural Products, 1999).
3. Present study
The CH
2Cl2 extract of the aerial parts of T. plicata (1.1 kg) was subjected to BiotageTM75#ash chromatography (silica gel, eluted with a step gradient of increas-ing polarity: n-hexane }EtOAc } MeOH) to yield nine fractions (1000 mL each). Reversed-phase preparative HPLC (C
18 preparative column, eluted with a gradient-water: acetonitrile: 0.1% TFA in acetonitrile"40 : 50 : 10 to 30 : 60 : 10 in 25 min,
55 mL/min., detection at 210 nm) of the #ash fraction 3 (30% EtOAc in n-hexane) yielded totarol (1, 113.9 mg) (Ying and Kubo, 1991), totaradiol (2, 4.1 mg) (Ying and Kubo, 1991), ferruginol (3, 42.1 mg) (Nakanishi et al., 1983) and yatein (4, 13.6 mg) (Harmatha et al., 1982). Similar puri"cation of #ash fractions 7 (75% EtOAc in n-hexane) and 8 (100% EtOAc) a!orded, respectively, calendin (5, 5.5 mg) (Okada et al., 1994), and vomifoliol (6, 18.7 mg) (Bhakuni et al., 1974). Structures of all these compounds have been determined on the basis of UV, 1H NMR, 13C NMR and LC-MS data, and direct comparison with the respective literature data.
4. Chemotaxonomic signi5cance
To our knowledge, none of the compounds (1}5) described here has previously been isolated from T. plicata. Totarane-type (1, 2) and abietane-type (3) diterpenes
occur in many species ofCupressus(Cupressaceae) andPodocarpus(Podocarpaceae) (Dictionary of Natural Products, 1999). Occurrence of totarane-type diterpenes in Thuja, as demonstrated in this paper, is noteworthy. Yatein (4) is a dibenzylbutyrolac-tone-type lignan. This type of lignans is well distributed in spermatophytes, and also is not rare in Gymnosperms (e.g. hinokinin, hibalactone, matairesinol). Calendin (5) and vomifoliol (6) are of widespread occurrence in the plant-kingdom (Dictionary of Natural Products, 1999).
Acknowledgements
We thank David Thomas for his assistance with LC-MS data. BBSRC is thanked for partial"nancial assistance for purchasing Bruker DRX500 NMR spectrometer.
References
Bhakuni, D.S., Joshi, P.P., Uprety, H., Kapil, R.S., 1974. Phytochemistry 13, 2541.
Dictionary of Natural Products, 1999. CD-ROM Version 8:1, Chapman & Hall, Boca Raton, FL, USA. Harmatha, J., Budesinsky, M., Trka, A., 1982. Coll. Czech. Chem. Comm. 47, 643.
Nakanishi, T., Miyasaka, H., Nasu, M., Hashimoto, H., Yoneda, K., 1983. Phytochemistry 22, 721. Okada, N., Shirata, K., Niwano, M., Koshino, H., Uramoto, M., 1994. Phytochemistry 37, 281. USDA-ARS-GRIN database, 2000. National Germplasm Resources Laboratory, Beltsville, MA, USA.,
available on-line at: www.ars-grin.gov/cgi-bin/npgs/html/taxdump.pl?Thuja#plicata Ying, B.P., Kubo, I., 1991. Phytochemistry 30, 1951.
