Oleum foliorum Matico. - Maticool. - Essence de Matico.

Origin. Piper angustifolium, Ruiz et Pavon (Artanthe elon-gata, Miq.), the matico tree, which is indigenous to South America, is regarded as the mother plant of the matico leaves. Inasmuch as the name matico is applied to a number of plants, the leaves of which can scarcely be distinguished from those of the above-named plant, it is not surprising that confusion frequently occurs, and that at times the genuine leaves cannot be had at all. A superficial examination of the matico leaves as imported for a number of years reveals but little external difference from leaves as formerly put on the market, but there is a material difference in the amount and quality of the oil which they yield. The cause of this lies in the fact that at present no uniform matico leaves, i.e. originating from one and the same plant, can be obtained. At the suggestion of Prof. H. Thorns1), of Dahlem-Berlin, this vegetable drug has been carefully examined by Professor Gilg, of Dahlem-Berlin, and by Professor Casimir de Candolle, of Geneva. They have ascertained that the commercial drug includes the leaves from the following plants:

1) Berl. Berichte 39 (1906), 656.

Piper angustifolium, Ruiz et Pavon.

Piper camphoricum, Cdc.

Piper lineatum, Ruiz et Pavon.

Piper angustifolium var. Ossanum, C.DC.

Piper acutifolium, Ruiz et Pavon var. subverbascifolium.

Piper mollicomum, Kunth.

Piper asperifolium, Ruiz et Pavon.

The yield of oil obtained upon distillation from these leaves varied between 0,3 and 6 p.c.

Properties of the Commercial Oils. The oil distilled in former years had a specific gravity of 0,93 to 0,99 and was slightly dextrogyrate. It was a viscid, more or less dark-colored liquid, the odor of which reminded one of both cubebs and mint.

The oil distilled in recent years is light-brown, and varies in its properties, as might be expected from the variation of the leaves from which it is distilled. d15o 0,940 to 1,135; aD - 27°28' to + 5°34'; nD20o 1,496 to 1,529; A.V. up to 4; E. V. 2,5 to 5,1; E. V. after acetylation 26 to 47. The solubility likewise varies greatly. Frequently the oil is soluble in 3 vols, of 80 p.c. alcohol, but occasionally 25 and more vols, are required. In some instances solution can be effected with 0,3 vol. of 90 p.c. alcohol, in other instances 6 vols, are required and even then the solution may be turbid.

For the properties of the oils distilled from material identified botanically, see p. 306.

Composition of the Commercial Oils. Matico camphor, the only known constituent of the older2) matico oil, was discovered by Fluckiger1). He obtained it by distilling off that portion of the oil passing over below 200°, when the camphor separated from the residue in hexagonal prisms 2 cm. in length and 5 mm. in thickness. Frequently this camphor crystallized from the oil when cooled.

1) Arch, der Pharm. 247 (1909), 591 (with 7 illustrations).

2) Whether the "old" matico oil from which the matico camphor used to separate, was distilled from the genuine matico leaves from Piper angusti-folium, Ruiz et Pavon, must remain undecided.

Matico camphor, when pure, is colorless and tasteless. It is soluble in alcohol, ether, chloroform, benzene, and light petroleum. The melting point of the crystals, which belong to trapazoedric tetartoedric division of the hexagonal system-), melt at 94°. Optically active3), the [a]D of the molten camphor, computed for 15° is - 29,17°. [a]D for the chloroform solution at 15° is - 28,73°. The specific angle of rotation of the crystals themselves is about eight times as great and, computed for a plate 100 mm. in thickness, is - 240°.

Basing his supposition on an elementary analysis, K. KuglerJ) thought that matico camphor might be identical with ethyl camphor C10H15(C2H5)O. This, however, is not the case, for, as H.Thoms5) has shown, matico camphor is a sesquiterpene alcohol which, when boiled with 25 p.c. sulphuric acid, yields a blue sesquiterpene C15H24.

Matico oil distilled in recent years contains no matico camphor. From an oil (d15o 1,077; aD - 0°25') distilled by Schimmel & Co.6) there separated a substance which, after repeated crystallization from light petroleum, melted at 62° and proved to be asarone (m. p. of dibromide 85 to 86°; m. p. of asarylic acid 144°). When oxidized with permanganate, the oil yielded an acid melting at 174° (veratric acid?), seeming to indicate the presence of methyleugenol. It is more probable, however, that the acid in question was a mixture of the apiolic acids to be described below.

While examining the "heavy portion" of matico oil, E. Fromm and K- van Emster7) supposed they had isolated as principal constituent an unsaturated "matico ether", to which they assigned the formula of a methylbutenyl dimethoxy methylenedihydroxy benzene. Upon oxidation this matico ether yielded an aldehyde, and furthermore an acid.

1) Berl. Berichte 16 (1883), 2841.

2) Hintze, Tschermak's Mineralogische Mitteilungen 1874, 227.

3) H. Traube, Zeitschrift f. Krystallographie 22 (1893), 47.

4) Berl. Berichte 16 (1883), 2841.

5) Arbeiten a. d. Pharmaz. Institut Berlin 2 (1905), 125. 6) Report of Schimmel & Co. October 1898, 33.

7) Berl. Berichte 35 (1902), 4347.

Later Thorns1) took up the investigation of the heavy matico oil and found, besides the matico ether, a hydrocarbon which congealed at - 18°, also another phenol ether. As shown by Thorns, the so called matico ether consists of two apiols, viz., of smaller amounts of parsley apiol, and of dill apiol (see vol. I. pp. 490 and 491) as principal constituent. Accordingly two isomeric apiolic acids, melting at 175 and 151° respectively, resulted upon oxidation. The parsley apiol was identified by reduction of the isomerized phenol ether with sodium and alcohol, methylation of the resulting phenol, and nitration of the ether. The nitro compound was identical with the 1-propyl-2,3,5-trimethoxy-4-nitrobenzene.

An oil distilled in 1907 by Schimmel & Co. from Peru matico leaves (d20o 0,948; aD - 16° 40') was likewise examined by H. Thorns2). It was free from ketones, contained 0,1 p.c. of phenols and 0,7 p. c. of acids, principally palmitic acid. Possibly the oil contained limonene and dill apiol, but their presence could not be positively established. Fraction 136 to 140° (14 mm.) contained a sesquiterpene closely related to cadinene and caryophyllene; judging from its molecular refraction, it belongs to the group of dicyclic sesquiterpenes. Its properties are: b.p. 138 to 139° (17 mm.); d0,914; nD21o 1,512537; n21o 1,50808 (red H-line); mol. refr. 66,52.

Still another oil, distilled by Thorns with a yield of 0,4 p.c. from leaves obtained from a Hamburg firm, revealed very different properties: d 0,9185; aD - 4°55'. The oil contained 0,8 p.c. of phenols, 4 p.c. of acids (principally palmitic acid), a small amount of aldehydes, likewise dill apiol. An examination of the leaves showed that those distilled by Schimmel & Co. differed throughout from those obtained from Hamburg by Thorns. Neither were the leaves of the same parcels uniform.

1) Arch, der Pharm. 242 (1904), 328. - The oil used for this investigation was distilled by Schimmel & Co. from leaves which, according to Prof. Gilg, were genuine matico leaves from Piper angustifolium, Ruiz et Pavon.

2) Ibidem 247 (1909), 591.

Properties and Composition of Matico Oils of known botanical Origin.