3,4-dinitrophenylhydrazone, m.p. 251 dec. [Calcd. I \ A SYNTHESIS

Hydrolysis of this ester with 6 N hydrochloric acid gave p-formylcrotonic acid' (IV) ,. 3,4-dinitrophenylhydrazone, m.p. 251 dec. [Calcd. for C1~HIaN4...
0 downloads 0 Views 250KB Size
June 20, 1955

COMMUNICATIONS TO THE EDITOR

230 m p , E 8,000 (trans) was consistent with the ethyl 6-formylcrotonate structure.6 The 2,4-dinitrophenylhydrazone melted a t 199-200’ [Calcd. for CiSH14N406: C, 48.45; H , 4.38; N, 17.37; CzHsO ( l ) , 13.9. Found: C, 48.38; H, 4.67; N, 17.03; C2H60,12.41. Hydrolysis of this ester with 6 N hydrochloric acid gave p-formylcrotonic acid’ (IV) , 3,4-dinitrophenylhydrazone, m.p. 251 dec. [Calcd. for C1~HIaN4O6: C, 44.90; H, 3.43; N, 19.03. Found: C, 45.06; H, 3.55; N, 18.891. This 2,4dinitrophenylhydrazone did not depress the melting point of the same derivative obtained from the periodate oxidation product of base-treated 11. The infrared spectra of the two 2,1-dinitrophenylhydrazones were identical. The periodate oxidation of base-treated I1 with formation of acetaldehyde in conjunction with previous information indicated the presence of the grouping

3423

ribofuranose-1-phosphate. Also, evidence is presented which indicates that the configuration of the phosphate residue a t C1in the synthetic sample is p, in contrast with the CY configuration of a sample of ribose-1-phosphate prepared by the action of the fish muscle riboside phosphorylase*on guanosine. 2,3,5-tri-O-benzoyl D-ribofuranosyl-1-bromide, prepared according to Ness, et al.,5was treated in benzene solution a t 5-8’ with one equivalent of triethylammonium dibenzyl phosphate. Triethylamine hydrobromide which separated was removed by centrifugation and the sirup, presumably 11, obtained after evaporation of benzene, was hydrogenated a t 0’ in anhydrous methyl alcohol, using freshly prepared 15% palladium-carbon catalyst. The methanolic solution of I11 was diluted with water and brought to and maintained a t pH 10.5.

-C-OH

I

HC-O-

\

CHI

The position of the other hydroxyl on C1 has already been shown. The isolation of acetaldehyde and 8-formylcrotonic acid by degradation of I1 is proof of a six carbon chain in cladinose. The appearance of a,@-unsaturationin I1 after base treatment indicates the @-positionof the methoxyl group (C3 in cladinose). The position of the second CCH3 group in IT (C, in cladinose) is shown by formation of IV, and this fragment also indicates that base treatment of I1 eliminates the methoxyl group, These facts are consistent only with structure I for cladinose.

OH

OH

I

OR OR 11, R = benzoyl, R’ = benzyl 111, R = benzoyl, R’ = H

Debenzoylation was complete after ca. 3 hours and ribose-1-phosphate was isolated as the barium salt and purified by the method of Kalckar‘; yield on a 2-g. scale, 20%. A n a l . Calcd. for C5H908PBa. (6) T. Y.Shen and M. C. Whiting, J . Chem. Soc., 1772 (1950). (7) This compound has been reported from a natural product, but it 1HzO: ribose, 39.1; P, 8.07. Found: ribose,6 was evidently not identical with the one isolated here: see I . J . Rinkes, 35.5; P,?7.9. The sample was non-reducing8 and Rec. trau. chim., 48, 1093 (1929). was free from inorganic phosphate.g Paper chromaLILLYRESEARCH LABORATORIES PAULF. WILEY tography in several solvent systems showed the 6, INDIANA OLLIDENE WEAVER INDIANAPOLIS product to be homogeneous and identical with the RECEIVED MAY20, 1955 enzymatically prepared sample of ribose-1 -phoshate.^ Furthermore, the two samples showed A SYNTHESIS OF ~-D-RIBOFURANOSE-I-PHOSPHATEidentical rates of hydrolysis in 0.1 M perchloric acid Sir: a t room temperature. They were found to be much Since the isolation by Kalckar‘ of ribose-l-phos- more labile than the following isomeric phossynthesized as phate as a product of the enzymatic “phosphoroly- phates : D-ribopyranose-1-phosphate, sis” of certain nucleosides, two other related ribose the crystalline barium salt from 2,3,4-tri-O-acetylderivatives have been discovered. Ribose-l,5- ribopyranosyl-1-bromide, ribose-2-phosphate,lo ridiphosphate2 has been shown to be the coenzyme bose-3-phosphatelO and ribose-5-phosphate. Enin the phosphoribomutase-catalyzed isomerization zymatic tests on the natural and the synthetic samof ribose-1-phosphate to ribose-5-phosphate and 3- ples of ribose-1-phosphate were carried out as folphosphoribose-1-pyrophosphate3 (I) has been dem- lows: Each sample (7.35 pM./cc.) was incubated onstrated to be a precursor in the enzymatic a t 37’ with the fish muscle riboside phosphorylase synthesis of nucleoside-5’-phosphates. Although in the presence of excess of hypoxanthine. After 3 the available evidence would appear to be con- hours, whereas ca. 90y0 of the natural sample had clusive as regards the location of the phosphate disappeared, with the concomitant liberation of an groups in these substances, the configurations a t C1 (4) H. 1,. A. Tarr, Fed. Pvoc., 14, 291 (1955). (5) R K. Ness, D. W. Diehl and H. G. Fletcher, J r , THISJ ~ I J R N A I . , of the ribose moiety remain unknown. As part of our work aimed at the chemical synthesis of these 76, 763 (1954). (6) A . H. Brown, Arch. Biochem. Biophys., 11, 269 (1946). compounds, we wish to report a synthesis of D(7) R . A. Bonar and E. L. Duggan, J . Bid. Chem., 212, 697 (1955). (1) H. M. Kalckar, J . Bioi. Chem., 167, 477 (1947). ( 2 ) H. Klenow, Arch. Biochem. Biophys., 46, I86 (19.53). (3) A. Kornlierg. I. Lieberman and I V > IV. Aistudy of the reaction time-course of the pyridine salts of the natural and synthetic samples of ribose1-phosphate showed the formation of V and VI13 from the natural material only, thus showing that the latter has the a-configuration. Further work to confirm this assignment is in progress. lye wish to thank Dr. H. L. A. Tarr for generous supplies of the enzymatically prepared samples of ribose-] -phosphate and for carrying out the enzymatic tests, This work was carried out under a 111) C. A . Dekker and H. G . Khorana. Tnrs J O W R S A L , 76, 3322 ( 1 9 5 4 ) ; G. L l . Tener and H. G. Khorana, ibid.. in press. (12) For example, 7.: vol. of 95ff ethyl alcohol plus 3 vol. oi 1 JZ ammonium acetate solution, A , C . Paladini a n d L. F. I,eloir, Aiochenz.

J . , 51, 426 (1952). (13) This relatively stable phosphate a reaction period of 19 hours.

W:I,

thc major product a f t e r

Vol. i 7

I/-\'

OH OH

\I

Consolidated Grant from the National Research Council of Canada, Ottawa. BRITISHCOLUMBIA RESEARCH COUSCIL R. S. ~ V R I G H T UNIVERSITY OF BRITISHCOLUMBIA H . G. KHORANA ~TAXCOUVER 8, B. C., CANADA RECEIVEDMAY19, 1955

BOOK REVIEWS Metal Physics and Physical Metallurgy. Volume 11. The Theory of Cohesion. An Outline of the Cohesive Properties of Electrons in Atoms, Molecules and Crystals. By M . A. JASWOX, M.A., Ph.D., Dept. of Mathematics, Imperial College of Science and Technology, London. Interscience Publishers, Inc., 250 Fifth Avenue, New York 1, K. Y. 1954. viii 215 pp. 14.5 X 22 cm. Price, $5.75. This book is primarily a discussion of the quantum mechanical theory of cohesion in systems for which quantum mechanical effects are of predominant importance. It begins with a presentation of the Schroedinger theory of quantum mechanics and the theories of the hydrogen and helium atoms. The author then proceeds to a detailed study of the hydrogen molecule and the hydrogen molecule ion, and a less detailed discussion of the treatment of more complicated molecules. A long section on the cohesion of metals is followed by a shorter section on covalent structures which ends the book. S o discussion is given of the cohesion of ionic solids, possibly because, although this is the one class of solids for which cohesion theory is relatively satisfactory, i t is just the one for which quantum mechanical effects are least important. It is clear from the outlitie abovc t h a t Dr. Jaswon's book traverses a very wide area of subject matter. Severtheless, the book is by 110 means the ponderous tome which might be suggested by the table of contents. As a consequence he has had to limit himself to thorough treatments of some few subjects and cursory treatments of others. I n a general way he has done this deliberately and with a proper balance between the amounts of detailed and cursory considerations. The material of which this book is constituted gives every appearance of heing well thought out, b u t the book as a I\-liolc does not. I t is iirver c l w r , for instancr, to what

+

kind of reader the book is addressed. Thus the entire first third of the book consists of a n elementary introduction to quantum mechanics. The reader to whom this material is useful would doubtlessly be too inexperienced in the use of quantum mechanics to benefit very much from the rest of the book. The discussion of molecular binding is probably the best section of the book for the reader who is well acquainted with the use of quantum mechanics but knows little about its application to molecular systems. In this section there seems to be the happiest blend of qualitative exposition with quantitative discussion of important simple cases. However, the writer substantially ignores the contributions of Lowdin to the subject a n d , as elsewhere in the book, seems almost completely unaware of a large amoutit of the American work. The section on metallic cohesion is poorer. The material is somewhat disorganized, and the whole section apparently suffers from the lack of a point of view. The final section oii covalency struck the reviewer as being well written, but out of place, in t h a t i t should have preceded the section 011 metals, since metallic systems are the only ones treated from the loose binding viewpoint. The reviewer enjoyed several sections of the book. 111 reading it he was struck by the singular difficulty involved in trying to write a n advanced textbook of this sort. I t seems in retrospect t h a t i t would have been better to soinewhat more formally separate the book into two treatises on molccular cohesion and metallic cohesion, respectively. \Yhile to the purist there may be no sharp distinction of this kind, the working theorists often make a methodological distinction. In this book the better parts seem to be those which would belong in the first treatise. WESTINGHOUSE RESEARCH LABORAT ORIBS E A S T PITTSRT~RGIT,I ' R S S A . I?. S A ~ A M S