3608
COMMUNIC.~TIONS TO THE EDITOR
Yul. 79
tively identified in our hydrolyzates, may be the product N F observed by Hock and Huber. It is interesting to note that the reactions leading to the formation of (I) are similar in character to two of the enzymatic reactions involved in polynucleotide synthesis.9, Recently Khorana, et al.," described a thymidine derivative analogous to (I) which they prepared by an entirely different procedure.
tatively to 5'-AMP, identified by paper chromatography and dephosphorylation by low concentrations of snake venom. The biological activity of (I) was not destroyed by incubation with pancreatic ribonuclease or spleen phosphodie~terase.~Through private communication with Dr. Leon Heppel, we learned that the structure we had tentatively proposed for (I) was identical with that proposed by Cook, Lipkin and Markham for a product isolated from the DEPARTMENT OF CHEMISTRY \TILLTAM H. COOK \\'BSHISGTOS UNIVERSITY DAVIDLIPKIX Ba(0H)t digestion of ATP.J This knowledge S T . LOUIS5 , ~ ~ ~ I S S O U R I ROYMARK HAM^^ prompted an exchange of information and samples were kindly provided for c o m p a r i ~ o n . ~ These (9) 31. Grunherg-Manago a n d S. Ochoa, THIS JOURNAL,77, 3165 samples were identical with (I) by the following (1955). criteria: (1) ultraviolet spectrum, (2) biological (IO) A. Kornberg, I. R. Lehman, M. J. Bessman a n d E. S.Simms, activity, (3) paper chromatography, (4) loss of Riochim. Biophrs. Acta, 21, 197 (1956). biological activity, when incubated with enzyme (11) H . G . R h o r a n a , et a l , THISJOWRNAL, 79, 1002 (1957). (12) On leave f r o m t h e rZgricultura1 Research Council Virus Kefractions from heart or brain, ( 5 ) quantitative search Unit. Cambridge, and wishep t o t h a n k t h e Wellcome Foundaconversion to 5'-AMP on incubation with a tion for a travel grant. partially purified enzyme from heart, and (6) conversion to adenosine on prolonged incubation with RECEIVED MAY6 , 195'7 large amounts of Crotalus adamnnteus venom (although, as reported,' moderate atnounts of Russell's viper venom did not attack (I)).fi
THE PROPERTIES OF AN ADENINE RIBONUCLEOTIDE PRODUCED WITH CELLULAR PARTICLES, ATP, Mg++, AND EPINEPHRINE OR GLUCAGON
Sir: Previous studies in this laboratory have shown that a heat-stable factor (formed by particulate fractions of liver homogenates in the presence of ATP, Mg++, and epinephrine or glucagon) stimulated the formation of phosphorylase in supernatant fractions of homogenates.' This factor was isolated by ion-exchange chromatography and proved to be an adenine ribonucleotide (I).l Similar or identical compounds have been isolated from heart, skeletal muscle and brain. Crystals formed when 2 X A1 aqueous solutions of (I) were chilled a t acid pH. (I) was not attacked by several monoesterases' and upon titration with alkali exhibited no buffering capacity between pH 5 and pH 8. Descending paper chromatography, using an ethanol-ammonium citrate (pH 4.4) solvent system, revealed that (I) moved more rapidly than 5'-XMP, but more slowly than adenosine. Heating a t 98" for more than 60 minutes in 1 Ar HC1, or more than 40 minutes in 1 N NaOH, was required to destroy completely the biological activity of (I). Biological activity of (I) was lost only after relatively prolonged heating a t 98' in 0.05 N HC1 in the presence of Dowex-50 (H+). The major products of such treatment, amounting to 85yc of the total, were (1) adenine, identified by ion-exchange chromatography and ultraviolet spectrum, and (2) a mixture of ribose-3-phosphate (60%) and ribose-2phosphate (40y0), identified by ion-exchange chromatography in the presence of borate.2 However, the biological activity of (I) was lost rapidly on incubation with crude or fractionated extracts of heart or brain. In the presence of a partially purified enzyme from heart, (I) was converted quanti(1) T \T Rall, E W Sutherland and J Berthet, J Bfol Chem 224, 403 (105;) 0)J S K h q m a n d W E L o h n , THISJ O U R N A L , 75, 1153 (1953)
I
(3) We t h a n k Dr. Leon Heppel of t h e National Institutes o f Health, Bethesda, Maryland, f o r supplying a sample of purified spleen phosphodiesterase, a n d for t h e information regarding t h e similarity of ( I ) with t h e compound reported i n t h e accompanying paper b y TT. H Cook, D. Lipkin and R . M a r k h a m . (4) W. H. Cook, D. Lipkin a n d R. M a r k h a m , THISJ O l i R N h I . , 79, 3607 (1957). ( 5 ) W e t h a n k Dr. R o y M a r k h a m for sending these samples a n d for furnishing a sample of Cvotalus adamanteus venom. (6) T h i s investigation was supported (in p a r t ) b y a research grant No. H-2745 f r o m t h e National H e a r t I n s t i t u t e of t h e Public Health Service.
DEPARTMEKT OF PHARMACOLOGY
EARLIT,SUTHERLAXD SCHOOL OF MEDICINE WESTERNRESERVE UNIVERSITY T IT.RALL CLEVELAND 6, OHIO RECEIVED MAY13, 1957
UNEQUIVOCAL SYNTHESES OF DL-cZ'S-~, IO-METHYLENEOCTADECANOIC ACID (DIHYDROSTERCULIC ACID) AND D L - C ~ S -1,12-METHYLENEOCTADECANOIC ~ ACID'
Sir: The recen t interest regarding the structure of sterculic acid2-7 prompts us to record a t this time an unequivocal synthesis of DL-C~S-9, 10-methyleneoctadecanoic acid (I) and the demonstration of its complete identity with dihydrosterculic acid. '2'
H
H
\C/ H3C-(CH2)x(I) x and y
o/---\o-(CH2),-COOH 7; (VI) x = 5 ; y = 9
=
(1) Supported b y grants f r o m t h e American Cancer Society, recommended b y t h e Committee on Growth of t h e h'ational Research Council, a n d by t h e U. S. Public Health Service. (2) J . R . N u n n , J . Ckem. Soc., 313 (1952). (3) J. P. Verma, B. K a t h a n d J . S. Aggarwal, F a t w e , 176, 84 (1955). (4) P. K. F a u r e and J. C . Smith, J . Chem. Soc., 1818 (1950). ( 5 ) D. G. Brooke a n d J. C. Smith, Chent. a n d I n d . , 49 (1097). (6) B. A. Lewis a n d R . A, Raphael, ibid., 50 (1957). (7) V . V.N a r a y a n a n a n d B. C. L. Weedon, ibid., 394 (1957). ( 8 ) K. Hofmann, 0 . Jucker, W . R . Miller, A . C vtlng, J r . and F. Taussig, Tms J O U R N A L , 76, 1789 (1931).
