Citrus essential oil of Nigeria. Part V: Volatile constituents of sweet orange leaf oil (Citrus sinensis).

The volatile oils extracted from leaves of eight cultivars of Citrus sinensis (L) Osbeck were comprehensively analysed by a combination of GC and GC-MS. Fifty four constituents accounting for 82.3-98.2% were identified. Sabinene (20.9-49.1%), delta-3-carene (0.3-14.3%), (E)-beta-ocimene (4.4-12.6%), linalool (3.7-11.1%) and terpinen-4-ol (1.7-12.5%) were the major constituents that are common to all the volatile oils. In addition, a cluster analysis was carried out and indicated at least four different chemotypes for the C. sinensis cultivars.

epi-Cubebanes from Solidago canadensis.

GC-MS of the essential oil prepared by hydrodistillation of the green parts of a specimen of Solidago canadensis collected near Katowice, Poland, revealed two new sesquiterpene hydrocarbons. Their EI mass spectra resembled the mass spectrum of beta-ylangene (1) but the retention indices of the new compounds differed markedly from this known compound. After isolation of the new compounds by preparative GC their investigation by one- and two-dimensional NMR techniques resulted in the identification of 6-epi-alpha-cubebene (2) (minor constituent, 1.5%) and 6-epi-beta-cubebene (3) (major constituent, 20.5%).