From the leaves of Piper lineatum, Ruiz et Pavon, H. Thorns1) obtained 0,44 p.c. of a volatile oil (9,5 g.). Under 15 mm. pressure it boiled chiefly between 140 and 160°, and appeared to consist mainly of sesquiterpenes. The principal fraction had the following constants: d 0,958; aD + 8°45'. Neither camphor nor phenol ethers could be identified.
198. Oil of Piper acutifolium Ruiz et Pavon var. subverbascifolium.
A few years ago there appeared in the Hamburg market a new variety of leaves labelled as being derived from Piper Mandoni, DC. According to H. Thorns1), it consisted largely of the leaves of Piper acutifolium, Ruiz et Pavon var. subverbascifolium, mixed with a few leaves of Piper mollicomum, Kunth. and Piper asperifolium, Ruiz et Pavon. From these leaves 0,8 p. c. of oil were distilled which had the following constants: d20o 1,10; aD + 0°24'; [a]D + 0°21,8'; methoxyl content 21,8 to 22,1 p.c; acid content + phenols 1,5 p.c. After distillation in vacuum the oil, deprived of its acids and phenols, yielded the following fractions:
70 to 148°
148 to 153°
153 to 155°
155 to 158°
Fraction I was shown to contain pinene, characterized by its nitrosochloride. Fraction II, after repeated distillation over sodium, boiled at 147 to 149° (12 mm.), and consisted largely of sesquiterpenes. Distilled over sodium, fraction III was shown to contain dillisoapiol (m. p. 44 to 45°). Fraction IV contained dillapiol, characterized by its tribromide melting at 110°.
1) Footnote 2, p. 306.
The same leaves were also distilled by Schimmel & Co. and the oil with a sample of leaves placed at the disposal of Prof. Thorns1). The leaves were the same with the exception that their base was rounded on both sides and heart-shaped in outline. Prof. C. de Candolle is of the opinion that these are the lower leaves of plants of Piper acutifolium, Ruiz et Pavon, var. subverbascifolium, that have not yet reached the flowering stage2).
The following constants were ascertained: d20o 0,939; aD+ 0°24'; [a] D + 0o 25,5'. The oil contained 1 p. c. of acid and phenols and a large percentage of sesquiterpenes. The methoxyl content was 4,2 p. c.
The oil was resolved into the following fractions:
I. b. p. 50 to 150° 80 mm. 50 g.
II. b. p. 130 to 155° 22 mm. 100 g.
III. b. p. 155 to 165° 22 mm. 30 g.
IV. b. p. 165 to 175° 22 mm. 7 g. Residue......... 4 g.
Fraction I contained pinene, characterized by its nitroso-chloride. Dillapiol, of which only traces were present, was identified by means of its bromide.
According to an elementary analysis, fraction 117 to 119 (11 mm.; nD 1,4714) consisted of an alcohol C10H16O which causes the decided odor of this matico oil. An additional constituent, making up about 55 p.c. of the oil, is a sesquiterpene of the following properties: d20o0,916; aD - 10°50'; nD 1,50542.