Oct. 5, 1963
COMMUNICATIONSTO
to obtain evidence as to whether a single intermediate is involved (which returns with partial loss of configuration) or if two intermediates are i n ~ o l v e d ' ~ (one which returns with preservation of configuration and the other with partial or complete loss of configuration). We also have examined the solvolysis product, p chlorobenzhydrol. For solvolysis in 80% acetone the alcohol is 8% as optically pure (retention of configuration) as the average optical purity14 of the ester from which it was derived. This means that solvolysis proceeds with 92% loss of configuration and 89;', retention of configuration. Solvolysis in 9 0 ~ oacetone proceeds with 10% retention of configuration. I n this connection i t is significant that control experiments demonstrated that (a) solvolysis involves a t least 99% alkyl-oxygen cleavage and (b) the alcohol does not undergo any change (racemization or oxygen exchange) under the conditions of the solvolysis. The partial retention suggests that the present solvolysis is related to the microscopic reverse of the cleavage of a-phenylethyl aryl ethers with hydrogen chloride reported by Hart and co-workers.15 Acknowledgment.-This work was supported in part by a grant from the National Science Foundation, Grant No. G193244, and in part by the Research Committee of the Graduate School with funds given by the. Wisconsin Alumni Research Foundation. (13) See S. Winstein, P. E. Klinedinst, Jr,, and E. Clippinger, J . Ana. Chem. Soc., 83, 4986 (1961). (14) Determined a s described by S. Winstein and D . Trifan, i b i d . , 74, 1154 (1952). (15) H. H a r t and R . J , Elia, i b i d . , 83, Y85 (19G1); H. H a r t and H. S. Eleuterio, i b i d . . 76, 1379 (19.54). See also K. Okamoto, K. Takeuchi, and H. Shingu, Biril. Chem. Soc. J a p a n , 95, 525 (1962). ( l a ) (a) Kational Science Foundation Fellow, 1961-1962; Shell Foundation Fellow, 1960-lYG1. (b) Sational Science Foundation Fellow, 19591962; Minnesota Mining and Manufacturing Company Fellow, 1Y62-1963.
THE
3061
EDITOR
Natural crystalline viosamine hydrochloride was isolated as previously described,' m.p. 132-138' dec., [ a j 2 ' ~ -9' initial + 4-21' (24 hr., c 1, HzO). Synthetic viosamine hydrochloride was prepared starting with methy~-6-deoxy-4-tosy~-a-~-galactopyranoside dibenzoate3 (I), m.p. 157-158'. Treatment with azide ion4 followed by reduction with platinum catalyst and saponification with barium hydroxide gave methyl-4,6-dideoxy-4-amino-a-~-glucopyranoside (II), m.p. 117-118'; +144' (c 0.85,HzO). The crystalline N-acetate I11 was prepared, m.p. 188-189.5'; [ a I 2 ' ~ +151" ( c 0.43, %O). The free amine I and the N-acetate TI1 were subjected to periodate studies to confirm their structure; I1 consumed 2 moles of periodate a t a rate essentially identical with that of methyl-a-D-glucopyranoside. The N-acetate 111 consumed one mole of periodate a t a much slower rate.
II
HO
c=o
CsHs
I1
C,H/
I
-1
I
FH3
CH3 c-
HO
OH IV
OH
HO I11
Many attempts to hydrolyze the a-methyl glycoside I1 failed to give a crystalline product, as did the many attempts to convert the natural viosamine into its a-methyl glycoside. Hydrolysis of the a-methyl glycoside N-acetate I11 was successful, using 2.5 N HARLAN L. GOERIXG hydrochloric acid for 6.5 hr. a t 100'. DEPARTMEKT O F CHEMISTRY Crystalline ROBERTG. B R I O D Y ~ ~synthetic ~ USIVERSITY OF WISCOSSIS viosamine hydrochloride (IV) was isolated JEROME F. LEVY'^^ MADISON, WISCOXSIN in Byo yield after cation exchange chromatography, m.p. 130-138' dec., [ a I 2 ' ~-12', 8 min. + +20' (22 hr., c 0.76, H2O). The decomposition point and optical rotation data correspond with the natural The Identification and Synthesis of the 4-Aminosugar material. The infrared spectra of the natural and from Chromobacterium violaceurn synthetic material were superimposable and the Xi Sir: values were identical in three systems: l-butanolWe wish to report the complete identification and acetic acid-water ( 5 :1:a), Rf 0.14; phenol-water synthesis of viosamine, 4,6-dideoxy-4-amino-~-g~ucose, (3: l), Rr 0.27; and l-butanol-ethanol-water-amisolated from the lipo-polysaccharide of C. violaceurn, monium hydroxide (5 : 1.4:3 : 0. l), Rf 0.44. NCTC 7 9 l i . This 4-aminosugar represents the The n.m.r. spectrum of the free aminosugar hydrofirst of a new class of carbohydrates isolated and chloride in deuterium oxide supported the glucoidentified from the special polysaccharides of bacteria. configuration. Further, we suggest that this class of carbohydrate Acknowledgment.-Supported by Grant N o . E1659may be of wide occurrence and importance, since, in 06 of the NIAID, United States Public Health Service, addition to its presence in the lipopolysaccharide of a t Duke University, and by Grant No. A-769 and CA C. violaceurn, the N,N-dimethyl derivative has been 3772 from the National Institutes of Health, a t Wayne shown to occur in the antibiotic amicetin, and since State University. the properties of viosamine indicate that it is identical (3) C . L. Stevens, P. Blumbergs, and F. A. Daniher, J . A m . Chein. SOL. with one of the new aminosugars isolated by Strominger2 85, 1552 (1963). as a thymidine diphosphate nucleotide conjugate (TDP(4) Cf.E. J. Reist, R . R. Spencer, B. R . Baker, and L. Goodman, Chem. X2) from Escherichia coli B. I n d . (Londnn), 1794 (1962), who show t h a t a 4-mesyl group in t h e galacto series is displaced with inversion b y azide ion in dimethylformamide solvent. (1) R . W. Wheat, E. L. Rollins, and J. M. Leatherwood, Biochem. Biop h y s . Res. Commzln., 9, 120 (1962). (2) T. Okazaki, R . Okazaki, J. L. Strominger, and S. Suzuki, ibid., 7, 300 (1962). A private communication from J. L. Strominger indicates S-acetyl viosamine appears t o be identical with X2 by paper chromatography in t h e three solvents reported in his article a n d b y comparison of infrared spectra a n d t h a t viosamine is identical with deacylated Xz in t h e three solvent systems of ref. 1.
DEPARTMENT OF CHEMISTRY CALVIN L. STEVENS WAYSESTATEUNIVERSITY PETERRLUMBERGS F. A . DANIHER DETROIT2, MICHIGAN DEPARTMENT OF BIOCHEMISTRY R . W. WHEAT DUKEUNIVERSITY MEDICAL CENTER A . RUJOMOTO DURHAM, h-ORTH CAROLISA E. L. ROLLINS RECEIVED AUGUST26, 1963
