Chemistry of Essential Oils

256 THE CHEMISTEY OF ESSENTIAL OILS

The oil distilled in Dalmatia and in Germany is of typically sage-
odour and is used for flavouring purposes, whilst that distilled in Spain
is distilled from Salvia trilobia, with possibly other species as well, and
more resembles spike lavender in odour than the ordinary sage of the
garden.
Pure Dalmatian or German sage oil has the following characters :—
Specific gravity 0-910 to 0'932
Optical rotation + 2° „ + 25°
Refractive index 1 4575 „ 1-4690
Esters as linalyl acetate.. .... 2 to 6 per cent.
Total alcohols as borneol 20 „ 25 „

It is soluble in 2 volumes of 80 per cent, alcohol.
Spanish sage oil has the following characters:—
Specific gravity .... 0*912 to 0-932
Optical rotation. + 10° to + 20° (rarely laevo-rotatory)
Esters as linalyl acetate. 5 to 20 per cent.
Total alcohols as borneol.. 20 „ 29 „

It is soluble in 6 volumes of 70 per cent, alcohol.
On fractionating German oil of sage H. Seyler x obtained 1 to 2 per
cent, of a first fraction boiling below 155°, which could be separated inta
three portions by repeated distillation over sodium. The fraction first
passing over, of the boiling-point 142° to 145° (d20<> = 0'80; nD = T4438;
aD = + 1° 40'), gave analyses corresponding to C 10 H 18. This hydro-
carbon, called " salvene," when oxidised with potassium permanganate,
yielded an acid, whose semicarbazone C 10 H 16 O 2 CON 3 H 3 melted at 204°,
and which possibly is identical with /3-tanacetoketonic acid (/3-thuja-
ketonic acid).
Salvene has probably the following constitutional formula :—

CH(CH 3 ) 2

HC'/ CH»

CH. CH 3

From the first runnings of a Spanish oil of sage no salvene could be
isolated.
Pinene and cineol are probably present in sage oil in small amount,
together with borneol, a small quantity of esters, and the ketone thujone.
Muir and Sugiura isolated a body which they named salviol, which is
now known to be identical with the body which has been named thujone.
Dextro-camphor is also present in traces. English distilled sage oil has
been said to contain cedrene, but the authenticity of the sample examined
is doubtful.
Salvia cypria, a native of the Island of Cyprus, yields an essential
oil having a camphoraceous odour. Two samples
2
gave the following
characters:—

*Berichte, 35 (1902), 550.^2 Bull. Imp. Inst. 11 (1913), 429.