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Essential Oils of Sagę Species 187

Fig. 1. Fingerprint gas chromalograms obtained from HS-GC-MS analysis of the volatile fractions of S. lauandulifblm and S. triloba. Selected (i.e., most abundant and/or best separated) peaks are labelled in accordance with the numbering in Table I

¹³C NMR Spectroscopy

The 100 MHz ¹³C NMR spectrum obtained from the volatile compounds isolated from S. tńloba is shown in Fig. 2. The main ałiphatic part (Fig. 2a) ranges from 8 to 48 ppm, with some lines between 55 and 58.5 ppm. Several distinct lines are present in the region from 99 to 127 ppm (Fig. 2b) and three further lines are also observed between 140 and 150 ppm. This part of spectrum is typical of aromatic carbon, but in this mixture of essential oils the lines arise, respectively, from olefinic and quaternary carbons in cyclic or unsaturated environments.

To observe the increase in resolution, the ¹³C NMR spectrum of the volatile compounds derived from S. laoandulifolia was recorded at 150 MHz with forty-thousand seans; the spectrum is shown in Fig. 3. Now, the ali-phatic region of the spectrum (Fig. 3a), and the olefinic and quatemary re-gions (Fig. 3b), are nearly evenly covered with fine signals indicating the presence of a rich variety of products in a broad rangę of concentrations. Expansion of a portion of an ałiphatic region of the 150 MHz ¹³C NMR spectrum (Fig. 4) reveals excellent resolution of single Lines, indicating the pos-sibility of identification of individual products in the mixture. The spectrum recorded for S. laoandulifolia at 150 MHz has many features comparable with those for S. tńloba recorded at 100 MHz, and the differences are mainly