Page:Indian Medicinal Plants (Text Part 2).djvu/334

Rumicin, C₁₅H₁₀O₄, crystallises from light petroleum in golden-yellow leaflets with metallic lustre, and melts at 186-188° ; the solution in caustic potash is purple-red, becoming colourless on exposure to carbonic anhydride, which precipitates rumicin. When heated with hydriodic acid, it yields chrysophano-hydro-anthrone, which is obtained from chrysophanic acid under the influence of the same agent.

Nepalin, C₁₇H₁₄O₄ , crystallises from glacial acetic acid in microscopic, orange needles, and melts at 136°; it is insoluble in alkali carbonates, but dissolves in caustic potash, forming a purple solution, which becomes colourless under the influence of carbonic anhydride. The solution in concentrated sulphuric acid is blood-red. The diacetyl derivative crystallises from glacial acetic acid in lustrous, brownish-yellow rhombohedra, which darken at 170°, and melt at 181°.

Nepodin, C₁₈H₁₆O₄, crystallises from a mixture of benzene light petroleum in long, greenish-yellow prisms, and melts at 158°. It dissolves readily in alkali carbonates, forming a yellowish-brown solution ; the solution in concentrated sulphuric acid is an intense, yellowish-red colour. The diacetyl derivative crystallises in pale-yellow rhombohedra, darkens at 180° and melts and decomposes at 168°.

These three constituents of Rumes nepalemis, of which nepalin greatly preponderates, are separated from one another by extracting the root with ether, removing nepodin by means of aqueous potassium carbonate, evaporating the ether, and extracting the rumicin from the residue with boiling acetone ; the nepalin remaining undissolved. (J. Ch. S. 1896 A. I. 573.)

Rumicin is chrysophanic acid, uncontaminated with methyl, chrysophanic acid, whilst nepalin is identical with nepodin, C l8 H 16 4 . (J. Ch. S. 1900 A. I. 41).

Sans. : — Chukra ; Shutavedhee.

Vern. : — Chuká Chukápálang (H. and B.) ; Shakkan-kirai (Tam.) ; Shukk-kura-ku (Tel.) ; Sukhasag (Assam) ; Ambut chuká (C. P.) ; Triwakka, khatbíri, khattítan, khatta mitha, saluní (Pb.); Chuká (Sind) ; Ambari, chukká (Deccan) ; Chuká (Bomb.).

Habitat : — Western Punjab ; on the Salt Range and Trans-Indus hills ; cultivated, and an escape in other parts of India.

A pale-green annual, monœicous, glabrous, 6-12in. high, dichotomously branched from the root, rather fleshy. Leaves petioled, elliptic, ovate or oblong, 3-5-nerved, base cuneate, rarely cordate or hastate, l-3in. acute or obtuse. Petiole as long as the blade. Racemes short, terminal, leaf-opposed, leafless, 1-1½in.;