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The latter would be expected to give 16-17 unsatu- a t 1100 cm.-' characteristic of the free sulfate ion disappears completely in the complex [Co(NH&ration readily; 3a,21-diaceto~y-A~~-pregnene-ll, 20-&one gives a strong PorterSilber reaction. The S04]C1. sulfuric acid spectrum showed an absorption maxiHowever, when the ligands are coordinated by an mum at 287 (A4-3-keto group) shoulder a t 390 mp. essentially electrostatic bond, the symmetry of the The mobility of the free substance and its ace- ion is practically maintained. Glycinometal comtate suggests the presence of four, possibly five, oxy- plexes are good examples in which carboxylate fregen atoms, two of which are in acetylatable hy- quencies (about 1600 cm.-l) have been observed, droxyl groups. In the propylene glycol-cyclohex- indicating that the carboxylate resonance in the ane system the acetate moved on paper a t approxi- glycino ligand is maintained nearly as in the case mately the same rate as 11-dehydrocorticosterone of potassium glycinate. If the structure in these acetate and considerably faster than substance S we should observe the acetate. When the 3-(2,4-dinitrophenylhydrazone) complexes were -C //O \O-M' of the acetate was heated one hour a t 60" in 0.02 N characteristic C=O frequency (about 1700 cm.-'), perchloric acid in acetic acid the absorption maxi- in place of the carboxylate frequency. mum a t 385 mp did not change in position. This O F CHEMISTRY result demonstrated the absence of a 6-acetoxy DEPARTMENT SAN-ICHIRO MIZUSHIMA UNIVERSITY OF NOTRE DAME group since in parallel experiments with 6cu- and NOTRE J . 1'. QUAGLIANO* DAME, INDIANA 66-acetoxy-11-desoxycorticosterone21-acetate 3RECEIVED AUGUST31, 1953 (2,4-dinitrophenylhydrazones)the absorption max* Member, Radiation Project operated by the University of Notre ima shifted from 387 and 381 to 398 and 400 mp. Dame and supported in part under AEC Contract AT(ll-1)-38. These conditions would be expected to cause loss of acetic acid from positions 1, 2 or i with increase in the wave length of the absorption maximum. STRUCTURE OF RESERPIN Hydrolysis of the acetate with citrus acetylase Sir: (courtesy of B. C. Bocklage and E. A. Doisy) gave a Reserpin, the new sedative and hypotensive product which was approximately 55 times as active principle of Rauwo1j.u serpentina Benth. has been in the bioassay as desoxycorticosterone acetate. isolated for the first time by Mueller, Schlittler and Paper chromatography showed the presence of two Bein.' The m.p., optical rotation, characteristic substances, one apparently com letely deacety- bands in the ultraviolet and infrared spectra and lated; crystals (rn.p. 163-164", .A:i 240 mp) of elementary analysis were also reported ; however, approximately the same activity as the crude mix- no empirical formula was assigned. ture were obtained from the dry ether. The secWe have been able to establish the empirical ond substance, which could be converted to the first formulas of Reserpin2 and its degradation products. by further treatment with acetylase, crystallized The alkaloid was isolated by chromatography of from acetone-petroleum ether, m.p. 217-2 19O ,X MeOH max the Oleoresin fraction on acid-washed alumina. 239 mp, and was approximately 25 times as active The repeatedly recrystallized material melted a t 264-265" (dec.) and was dried for eight hours a t as desoxycorticosterone acetate. THE1MAYO CLINIC V. R. MATTOX 120" and 0.05 mm. for analysis. Calcd. for C W H.L. MASON H4o09Nz: C, 65.11; HI 6.62; N, 4.60; OCH3 (6), A S D MAYOFOUXDATIOV K OCHESTER, MINNESOTA A ALBERT 30.59. Found: C: 65.31, 65.11, 65.00; HI 6.88, C . F CODE 6.83, 6.68; N. 4.79; OCHa, 30.22. Mol. ~ t . RECEIVED AUGUST24, 1953 Calcd. 608.67; found: 586 =k 20 (electrometric titration, +K'a 6.6 in 66% dimethylformamide) ; STRUCTURE OF LIGANDS IN INORGANIC COOR- 610 (X-ray methods), no C-methyl. The ultraDINATION COMPOUNDS BY INFRARED SPECTRA violet spectrum of Reserpin showed the following bands: Amax. 216 mp (log E = 4-79), hmax, 267 mp Sir: In addition to the active frequencies we have ob- (log e = 4.23), Amax, 295 mp (log E = 4.07), shoulder . my (log e = 3.99), A ~ n 286 . served the forbidden frequencies as weak infrared a t 225 mp, A ~ n 246 absorption for such symmetrical ions as NOa-, mp (log e = 4.00). The maleate salt of Reserpin SO4--, etc., when these ions are present outside melted a t 226-227" (dec.). Calcd. for C33H40the coordination sphere in complex compounds. 09N3C4H404:C, 61.31; H, 6.12; N, 3.86. Found: For example, the totally symmetric frequency of C, 61.5; H, 6.3; N, 3.83. Basic hydrolysis of the nitrate ion a t 1050 cm.-' has been observed Reserpin, using dilute sodium hydroxide in methas a weak infrared absorption in the complex, anol yielded two fragments. One was readily [Cu(SC(NHCH~)2]JN03,and that of the sulfate identified as 3,4,5-trimethoxybenzoic acid, identiion at 980 cm.-' in the compound [Cu(NH3),]- cal in each respect with an authentic sample (XS04.&0. The appearance of these forbidden ray patterns, infrared ultraviolet, m.p. and mixed symmetrical frequencies in absorption can be m.p.). The second fragment for which we propose explained as due to the deformation of the ions in the name Reserpic acid was isolated as the hydrochloride of an amino acid, m.p. 274-275" (dec.). the molecular field of the crystals. If such ions are coSrdinated to the central metal I t crystallized with one mole of methanol and was (1) J. M . Mueller, E. Schlittler and H. J. Bein, E z p e u i e n l i a , 8 , 338 ion of a complex, the symmetry is disturbed much more markedly and a spectrum quite different (1952). (2) Our Reserpin was spectrally identical with a sample obtained from that expected for the free ion is observed. through the courtesy of Dr. E. Schlittler of Ciba Pharmaceutical ProdFor example, even the strongest absorption band ucts, Summit, N. J.
