Brazil Wood
Brazil Wood.—A red dye-wood, the product of different species of Caesalpinia, growing in the West Indies and South America. Two varieties are known in commerce—1, the proper Brazil wood, said to be derived from Caesalpinia echinata Lam., and sometimes called Pernambuco or Fernambuco wood, from the province of Brazil, where it is collected; 2, the brasiletto, produced by C. brasilensis, L., and C. Crista, L., which grow in Jamaica and other parts of the West Indies. The former is the most highly valued. The Nicaragua or peach wood is also analogous to the brasiletto, and is said by Bancroft to be derived from a species of Caesalpinia. It is produced in the East Indies. Brazil wood is nearly inodorous, has a slightly sweetish taste, stains the saliva red, and imparts its coloring matter to water. It was formerly used in medicine, but has been abandoned as inert. In pharmacy it serves to color tinctures, etc., but its chief use is in dyeing. A red lake is prepared from it, and it is an ingredient in a red ink. Its dyeing properties are due to a crystallizable coloring principle, named brazilin or brasilin, C16H14O5. This, as usually obtained, is of a sulphur-yellow color, which it preserves in the dark, but in the sunlight, to which it is remarkably sensitive, changes to a reddish hue after a few minutes' exposure, and also more slowly in diffused daylight. The principle should, therefore, be kept in perfectly opaque vessels. It is now stated that when absolutely pure it is colorless, and becomes red on exposure to the air. The change is due to the formation of brasilein, C16H22O5, which can be prepared from the brasilin by a variety of methods, such as oxidation by nitrous acid, by alcoholic iodine solution, etc. Brasilin is sparingly soluble in water, yielding a sweet and almost colorless solution which is not changed by acids, but is deeply reddened by alkalies. In alcohol and ether it is somewhat more soluble than in water, giving a light yellow solution. Brasilin and hematoxylin (from logwood) are now recognized as related, each being derived from the pyrone nucleus C5H4O2, from which the two groups, the xanthone group and the flavone group, are also taken. The coloring principles of most dye-woods are now referred to this source. (Kupe, Die Chemie der natürlichen Farbstoffe, Braunschweig, 1900.)