54 
INDIAN MEDICINAL PLANTS. 
Pikrotoxinin, C 15 H 16 0 5 , is best obtained from pikrotoxin by brominating 
the latter, when in hot aqueous solution, with a slight excess of bromine 
water, and then, by means of zinc dust and acetic acid, removing the bromine 
from the monobromopikrotoxinin, which crystallises out ; it crystallises from 
hot water in colourless, anhydrous needles, but from cold aqueous solutions in 
rhombic plates containing 1H 2 0, melts at 200-201’, is readily soluble in all 
the usual solvents on warming, and also in cold alcohol or chloroform ; it is 
also soluble in alkalies, but is not reprecipitated on the addition of acids. 
Sulphuric acid develops an intense orange red coloration, and when hydro- 
gen ehloride is led into an ethereal solution of the compound, polymerisa- 
tion occurs, and pikrotox ide, melting at 308-310°, is formed. Aqueons 
solutions reduce ammoniacal silver nitrate in the cold, but it contains neither 
an aldehydic nor a ketonic group. It has an extremely bitter taste, and is 
the active principle of pikrotoxin ; its specific rotatory power [a]D=— 5'85°. 
Bromopikrotoxiuin, C 15 H ls BrO s . which is most readily obtained by adding 
bromine water to a hot, nearly saturated,, aqueous solution of pikrotoxinin 
until the solution remains permanently yellow, may be purified by recrystal- 
lisation from absolute alcohol ; it separates in glistening needles, melts at 
259-260° (Schmidt gives 250-255° ; Paterno and Oglialoro give 240-250°), and 
has [u]17/D= - 182-6°. 
Chloropikrotoxinin crystallises from alcohol in a mixture of needles and 
plates, melting at 272°. 
Iodopikrotoxinin, obtained by the action of iodic acid and a. solution of 
iodine in potassium iodide C 15 H u O d Ac 2 , as it can readily be obtained by the 
action of acetic chi '4de on pikrotoxinin ; it sublimes in slender needles 
melting at 254°— 255/ hnd forms an unstable compound with bromine. 
Pikrotin, C 15 H 18 0 7 , is best obtained from the filtrate from bromopikrotox- 
inin, part separating out on cooling, whilst the remainder may be obtained 
by evaporation ; it can he purified by several extractions with small 
quantities of hot chloroform, followed by recrystallisation from water ; it forms 
small, felted needles, or thick, rhombic prisms, melting at 248-250°, is readily 
soluble in absolute alcohol or acetic acid, but only sparingly in ether, 
chloroform, or benzene. Its specific rotatory power [a]D=— 64’7°, and it 
reduces Fehling's solution, etc., but only on warming. Its molecular formula 
has been determined by molecular weight determinations and by the analyses 
of its benzoyl and acetyl derivatives. 
Ilcitzoylpikrotin, C 15 H 17 0 7 BZ, crystallises from absolute alcohol in colour- 
less needles, melts at 236°, and is readily soluble in chloroform, sparingly in 
ether or alcohol. 
Elbe moylpikrotin, obtained when pikrotin (1 mol.) is heated with benzoic 
chloride (3 mols.) at 190°, crystallises from alcohol in needles melting on a 
hot aqueous solution of pikrotoxinin, crystallises from alcohol in colourless 
needles and melts at 198-199°. 
I romopikrotoxic acid, C lt H 15 Br0 5 -C00H-f HjO, is obtained when 10 per cent, 
potassium hydroxide solution is slowly added to finely divided bromopikro- 
toxinin suspended ih 10 times its weight of boiling water, until all has dis- 
solved ; on the addition of hydrochloric acid, the acid crystallises out in 
colourless needles, melting at 245-246°; it has no bitter taste, and is optically 
