serpentine

Description

This alkaloid has been isolated from Rauwolfia serpentina Benth and forms yellow plates from MeOH or EtOH. The earlier formula of C₂₀H₂₀0₃N₂ has recently been altered to that given above. The hydrochloride hydrate has m.p. l33-5°C or 248-260°C (dry);[α]⁴⁰_D + 188° (H₂0); nitrate, m.p. 172°C; nitrite, m.p. l65-6°C (dec.); perchlorate, m.p. 256°C; picrate, m.p. 26l-2°C and methiodide, 245-6°C. The base also yields a monobromo-hydrobromide, m.p. 257-8°C (dec.). On heating to 210°C it isomerizes to isoserpentine, colourless prismatic rods, m.p. 230-2°C yielding a hydrochloride, m.p. 271-2°C; [α]³⁴_D+ 168.08° (H₂0) and the picrate, m.p. 263-4°C.

Definition

serpentine: Any of a group of hydrousmagnesium silicate mineralswith the general compositionMg₃Si₂O₅(OH)₄. Serpentine is monoclinicand occurs in two main forms:chrysotile, which is fibrous and thechief source of asbestos; and antigorite,which occurs as platy masses. Itis generally green or white with amottled appearance, sometimes resemblinga snakeskin – hence thename. It is formed through the metamorphicalteration of ultrabasicrocks rich in olivine, pyroxene, andamphibole. Serpentinite is a rockconsisting mainly of serpentine; it isused as an ornamental stone.

Agricultural Uses

Serpentine is a mineral consisting of magnesium silicate. With a green and white color and a mottled appearance, this mineral looks like a snake's skin. Serpentine has a general composition of Mg₃Si₂O₅(OH)₄.

References

Siddiqui, Siddiqui., J. Ind. Chem. Soc., 8,667 (1931)
Siddiqui, Siddiqui., ibid, 9, 539 (1932)
Siddiqui, Siddiqui., ibid, 12, 37 (1935)