Cedrol (cedar camphor, cypress camphor), C15H260, has been found in oils of cedarwood (Juniperus virginiana), Juni-perus chinensis (?), cypress and Origanum smyrnaeum (?) as the dextrogyrate modification. M. p. 86 to 87°; b. p. 291 to 294° (ord. pressure), 157 to 160° (8 mm.); [a]D + 9o31' (in chloroform solution). Treated with phosphorus pentoxide or formic acid, it readily splits off water, yielding cedrene. The phenylurethane melts at 106 to 107°.4)
1) Semmler and Bode, Berl. Berichte 40 (1907), 1126.
2) Ibidem 1133.
3) Report of Schimmel & Co. April 1891, 65; October 1891, 45.
4) Report of Schimmel & Co. October 1906, 49; April 1910, 46.
Cubed camphor, C16H260, is reported to separate from oil of cubeb when the latter is exposed to the air for a long period. It is laevogyrate, melts at 68 to 70° and boils at 248° with loss of water. This loss of water can also be brought about readily by other means.
Ledum camphor, C15H260, has been obtained from the oil of Labrador tea in long, colorless needle-like prisms, melting at 104° and boiling at 281°. Its alcoholic solution is slightly dextrogyrate. It produces a toxic effect on the human organism. It is readily converted into the sesquiterpene ledene.
Patchouli alcohol or -camphor, C15H260, is an odorless constituent of patchouli oil from which it separates in crystals that melt at 56°. It is strongly Isevogyrate, [a]D - 97°42' (in chloroformic solution). Like a liquid compound from the same oil, which however deviates the angle of polarized light to a lesser degree, it readily looses water, forming patchoulene.
Atractylol, C15H260, separates from the oil distilled from the roots of Atractylis ovata. M. p. 59°; b. p. 290 to 292° (760 mm.); 162° (15 mm.); nD 1,51029 to 1,51101. It is distinguished from patchouli alcohol by being optically inactive. The odor is said to remind of that of lillies of the valley. If a few drops of sulphuric acid be added to a chloroform solution, a red-brown color is produced changing to violet. This alcohol also readily looses water yielding atractylene.
Guajol, C15H20O. This sesquiterpene alcohol is contained in the oil of the wood of Bulnesia Sarmienti and in that obtained from the wood known as "Kajoe garoe".1) Its properties are:
M. p. 91°; b. p. 288°; aD20o - 29,8°.
The properties of the compound obtained from Kajoe garoe deviate somewhat. Guajol does not loose water as readily as do some of the other sesquiterpene alcohols. When water is split off it yields the blue-colored guajene.
1) Eyken, Recueil des trav. chim. des P.-B. 25 (1906), 40, 44; Chem. Zentralbl. 1900, I. 841.
For guajyl methyl ether, obtained by the action of methyl iodide on guajol potassium, Gandurin1) found the following constants:
B.p.l41tol43°(9mm.); d 0o/4o 0,9513; d 25o/4o-0,9332; [a]D20o - 31,81°; nDl8.5o1,48963.
Matico camphor, C15H260, formerly obtained from the oil of matico leaves, is no longer found in this material. It crystallizes in thick, hexagonal columns melting at 94°; [a]D - 28,73° in chloroform solution. It looses water when heated for several hours with 50 p. c. sulphuric acid.
Sesquiterpene alcohol from eucalyptus oil. From the oil of Eucalyptus Globulus a sesquiterpene alcohol C15H260 of the following properties has been isolated:
M. p. 88,5°; b. p. 283° (755 mm.); [a]D - 35°29' (in chloroform solution).
When water is split off, two distinct sesquiterpenes are formed.
There can be no doubt that sesquiterpene alcohols are widely distributed in volatile oils. A number of compounds have been isolated which evidently belong to this group. Thus from oil of juniper berries a substance melting at 165 to 166°, from ylang-ylang oil one melting at 138°, and from the oil of Piper Lowong one melting at 164°. So far as the present stage of investigation seems to indicate, the presence of sesquiterpene alcohols may be suspected in the oils of Atlas cedar, Crypto-meria japonica, vetiver, paradise grains, paracoto bark, Nec-tandra Caparrapi, Maali resin, laurel leaves, camphor, copaiba balsam, pelargonium, neroli, angostura bark, opopanax resin, cascarilla, Aralia nudicaulis, asafetida, valerian, Spanish hops, and Blumea balsamifera.
In this connection several alcoholic constituents of volatile oils with more than 15 carbon atoms in the molecule should be mentioned:
Turmerol, C19H280, contained in oil of turmeric (b. p. 285 to 290°; d17o0,9016; [a]D + 33,52°); and an
1) Berl. Berichte 41 (1908), 4362.
Alcohol, C20H32O, isolated from the oil of Erythroxylon monogynum (m. p. 117 to 118°; [a]D + 32°28' in chloroform solution). This alcohol can be esterified quantitatively, the acetate melting at 72 to 73°.
The fact that the sesquiterpene fractions of certain oils are colored blue should not fail to receive mention. This blue color is most intense in the fractions boiling between 275 to 300°, though also observable in the lower fractions. The color varies from the most intense indigo-blue to greenish shades. As is the case with chamomile oil, the oil itself may be colored strongly blue. Certain oils obtained by the dry distillation of resins reveal a similar color, as do also some of the sesquiterpenes obtained artificially (guajene, atractylene). As to the cause of the color not the least is known. There would appear to be some indication, however, that it is due to the formation of oxy-dation products. The following list contains the names of those oils in which the blue color has been observed, viz., the oil of Piper Lowong, the oil from the berries of Piper Cubeba, the oil of Canada snake root, camphor oil, the oil of pichurim beans, Reunion geranium oil, the oils of guaiac resin, cedrella wood, damiana leaves, Aralia nudicaulis, Meum athamanticum, the root of Pimpinella nigra, Japanese angelica root, asafetida, galbanum resin, sumbul root, opopanax resin, patchouli, dilem leaves, valerian, kesso root, chamomile, wormwood, milfoil, European pennyroyal, Roman chamomile, Achillea coronopifolia, A. moschata, and elecampane.