Boehme

Traving M, Boehme M, Kipp L, SkIbowskI M, Starrost F, Krasovskll E E, Perlov A and Schattke W 1997 Electronic structure cfWSe2 a combined photoemisslon and Inverse photoemisslon study P/rys. Rev. B 55 10 392-9... 

Diethyl pyrocarbonate (DEP) [1609-47-8] M 162.1, b 38-40°/12mm, 160-163 /atm, d 1.119, Op 1.398. Dissolve in Et20, wash with dilute HCl, H2O, dry over Na2S04. filter, evaporate and distil the residue first in vacuo then at atmospheric pressure. It is soluble in alcohols, esters, ketones and hydrocarbon solvents. A 50% w/w soln is usually prepared for general use. Treat with great CAUTION as DEP irritates the eyes, mucous membranes and skin. [Boehm and Mehta Chem Ber 71 1797 1938 Thoma and Rinke Justus Liebigs Ann Chem 624 30 1959.]... 

Curare was first examined by Roulin and Boussingalt, who isolated a syrupy body, which they named curarine much later a similar substance was obtained by Buchner, - and in 1865 Preyer announced that he had obtained curarine and its salts in a well-crystallised condition, and by analysis of the platinichloride, ascertained its composition to be C10H35N. Sachs - was only able to obtain an amorphous alkaloid, to which he assigned the formula CigHjjN. The work of Boehm explained to some extent these discrepant results he examined all three varieties and showed that they differed in composition, and that the isolation of the various curarines as single substances required special processes. 

Tubocurarine chloride, C3jH4jOgN2Cl2.5H2O. Though Boehm was successful in obtaining a potent tubocurarine, he was unable to prepare it or any of its derivatives in a crystalline condition, and this was first achieved by King, who obtained tubocurarine chloride in microscopic leaflets, m.p. 274-5° (dec.), -f- 264-8° (dry salt, H2O). A saturated... 

Alkaloids of Pot Curare. This variety of curare is a dark brown, comparatively dry extract. According to Boehm, it contains protocurine, colourless hair-like needles, m.p. 306° (dec.), a base of low toxicity and yielding crystalline salts. A second alkaloid of similar type is protocuridine prisms, m.p. 274-6°, sparingly soluble in all ordinary solvents. The poisonous constituent is protocurarine, a red powder, easily soluble in water, and giving characteristic colour reactions with nitric acid and with oxidising agents in sulphuric acid, this latter reaction indicating a Strychnos spp. as a possible botanical source. 

The specimen examined by King - contained a mixture of alkaloids, which was partially separated by a special process into (a) non-quaternary bases, and (b) quaternary bases. From the former, which was a mixture of phenolic alkaloids, Boehm s protocuridine and a new isomeride of this, u oprotocuridine, were isolated. 

Alkaloids of Goukd ok Calabash Curare. The toxic constituent of this form, as prepared by Boehm, was an amorphous curarine to which the formula C gHjgONj was assigned. Gourd curare has been investigated in recent years by Wieland et aZ. and by Schmid and Karrer. ... 

Karrer and Matter have confirmed the presence of succinic acid as recorded by Boehm, and of protoeatechuic acid as found by Wieland, Konz and Sonderhoff and have added thereto, mesaconic acid as a constituent of calabash curare. 

The drug varies greatly in activity. The following lethal doses (mg. per kilo) have been recorded for rabbits pot curare 0-8 to 10-0, more commonly 2 to 3 tube curare 5 to 10 gourd curare 1-5 to 8-0, Boehm gave the... 

ZN(B)745 P Kreutzer, C. Weis, H. Boehme, T. Kemmerich, W. Beck, C. Spencer,... 

AGE1121 C. Boehme, P. R. Allen, M. Murray, and A. G. Orpen, Angew. Chem.,... 

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