potential 4 kV, and ionizing potential 70 V. IR spectra were recorded on a Perkin—Elmer System 2000 FT-IR Fourier
spectrometer in KBr pellets.
Isolation of Ricinine. Ground castor seeds (2.4 kg) were extracted on standing with acetone at room temperature.
The yield of oil after evaporation of acetone was 1 kg or 40% of the dry mass.
Defatted seeds were extracted with ethanol (85%). The ethanol was evaporated in vacua. The extract stratified into
two layers. The upper oil layer and lower aqueous layer were washed with ether, made basic with aqueous ammonia, and
repeatedly extracted with CHCl . The CHCl extract was dried over anhydrous sodium sulfate. The solvent was evaporated.
3
3
The solid crystals (2.1 g, 0.08%) are technical-grade ricinine.
o
Ricinine (1). Crystals are whitish-cream colored, mp 200-201 C (ethanol), R 0.20 (rosy spot) for TLC using
f
system 1.
+
Mass spectrum, m/z: 164 (M ) (100%), 146, 135, 121, 96, 93, 80, 69, 58, 51.
Mercuric Salt of Ricinine. Ricinine (0.14 g) was dissolved in warm distilled water (10 mL) and treated with mercuric
chloride solution (0.1%). The mercuric salt of ricinine precipitated. The precipitate was separated and recrystallized from
o
aqueous ethanol to give the mercuric salt of ricinine (0.08 g), mp 202-203 C.
Preparation of 2 from 1. Ricinine (1, 0.35 g) was dissolved in aqueous NaOH (10 mL, 5%), heated on a boiling-water
bath for 30 min, cooled, and acidified with H SO (5%). The precipitated white, fine, needlelike crystals (0.31 g) were
2
4
o
recrystallized from ethanol, mp 286-288 C (dec.), R 0.40 for TLC on Silufol using system 2.
f
Methylation of Ricininic Acid by Diazomethane. Ricininic acid (200 mg) was dissolved in dry methanol (65 mL),
treated with diazomethane in ether (50 mL), and left in a refrigerator for 48 h. The solvent was evaporated. The solid was
dissolved in CHCl (50 mL), washed with NaOH solution (2%), and dried over anhydrous Na SO . The solvent was evaporated.
3
2
4
o
The solid ricinine was recrystallized from ethanol, mp 200-201 C, yield 120 mg.
Preparation of O-Acetylricininic Acid. Ricininic acid (3.4 g) was treated with acetic anhydride (15 mL) and boiled
on a sand bath for 6 h. The reaction mixture crystallized entirely upon cooling. The crystals were vacuum filtered, washed with
o
+
acetic anhydride, and dried to give O-acetylricininic acid (3.35 g), mp 154-155 C (acetone). Mass spectrum, m/z: 192 (M ),
1
64, 148, 147, 121, 95, 84, 82, 66, 64.
Quantitative Determination of Ricinine in Castor Pulp. Ground pulp (30.0 g) was exhaustively extracted with
ethanol in a Soxhlet apparatus for 7-8 h. The ethanol extract was condensed to 50-60 mL and basicified with ammonia.
Ricinine was repeatedly extracted with CHCl in a separatory funnel (500-600 mL). The CHCl solution was shaken 5-6 times
3
3
with H SO (20 mL, 2%).
2
4
The acidic extract was basicified with ammonia and again extracted with CHCl . The CHCl extract was dried over
3
3
anhydrous Na SO and evaporated on a water bath. The solid is technical ricinine, yield 0.07% of the pulp mass, R 0.20 for
2
4
f
TLC on Silufol using system 1.
REFERENCES
1
.
Kh. Kh. Kholmatov, I. A. Kharlamov, P. K. Alimbaeva, M. O. Karriev, and I. Kh. Khaitov, Principal Medicinal
Plants of Middle Asia [in Russian], Meditsina, Tashkent (1984).
2.
3.
4.
D. A. Murav eva, Pharmacognosy [in Russian], Meditsina, Moscow (1991).
A. P. Orekhov, Chemistry of Alkaloids [in Russian], Moscow (1955).
D. A. Khashimov, Kh. G. Alimov, and P. Kh. Yuldashev, Khim. Prir. Soedin., 243, 845 (1988).
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Yuldashev
