2178
ROBERT SCIIAFFER AND HORACE S. 1snl;:r.L
C'ol. H 1
before. After rcmoving the liquid ammonia the product The drird (N&O4), conihinrd extracts wrre evaporated was extracted with chloroform and tlistillrd giving the hcpta- and the sirupy protlurt distillcd giving: fraction I . I ,3-tIi-00-methyl ticrivative V as a colorless liouid, 1.91 g., b.p. methyl-glycerol (0.102 g.), b.p. (bath temp.) 1 :ttni., 180(bath temp.) 18&190° (0.003 niiii.), ? Z ~ D1.4111, [ a I z 6 ~ 190", 7t3'D 1.4165. Iqraction 2 , a mixture of 1,hIi-OSIG.9' (pure liquid), +9.7" in methanol (c i ) . The sub- methyl-glycerol and 1,4-di-0-1rirtliyl-er~thritol (O.O(i7 g.), stance was insolublc in water. b.p. (bath temp.) 145160O (30 mm.), n a ' D 1.4223. Frac3 , 1,4-rli-O-nietliyl-er~tIiritol(0.044 g.), h.p. ( I x t h A n d . Calcd. for C18H3R010: C, Fj2.2; H, 9.25; OCHs, tion temp.), 180-191)" (30 mm.), T Z ~ 1.4355, D K f (butm-1-wl52.4. Found: C, 52.3; H, 9.25; OCH3,'*50.1. ethanol-water (4:1:5) 0.65. Hydrolysis of the Heptamethyl Ether V.-A suspension Treatment of fraction 1 (52 mg.) in pyridine ( 3 1111.) with of the methyl ether ( V . 1 6.) in N sulfuric acid (30 i d . ) was p-nitrobenzoyl chloride (150 nig.) as previously dcscri1)ed'O refluxed for 3 hr. when the clear solution had become op- afforded 1,3-di-O-tnethylglycerolp-nitrobcnzoate, m.p. and tically inactive. The solution was distilled a t atmospheric mixed n1.p. 41.5,'O after rccryst:illization from light petropressure and the first 5 ml. of distillate was treated with p - leum ether. nitropheiiylhydrazine'o whereby there was produced rapidly Fraction 3 (40 ing.) was tre:itcd in pyridine ( 3 1111.) with methoxyacctaldeliyde p-nitrophenylhydra~one,'~ m.p. and p-toluencsulfonyl chloride (150 m g . ) for 1 day at room teniperature and for 10 inin. at 80-8jo. The rcaction mixturr mixed n1.p. lIGo (after recrystallization from ethanolwater ( 2 : 3 ) ) . was cooled, poured into ice-water and the crystals of 1,4T h e aaueous, acidic distillation residue after removal di-O-methy1-2,3-di-0-tosyl-erythritol so formed were filtered, of the methoxyacetsldehyde-water azeotrope, was satu- washed with water and recrystallized from etlianol, 1n.p. rated with ammonium sulfate and extracted with ether. and mixed m.p. 140". A n d . Calcd. for C20HnsO&: C, 52.4; 11, 5.7; S , 13.9. (14) G. G r a n , Svenrk Papfierslidn., 56, 179 (1953). Follll~l: 52.2; II,5.8; s, 13.0. (1.5) N. L. D r a k e , H. M. Diivall, T. L. J : I C O ~ S , €I. T. Thompson a n d €1. M. Sonnichsen, 'I'IIIS JOURNAL. 60, 73 (1938). ST.PAUL,MINN.
c,
[CONTRIBUTION FROM DIVISION OF CIIDMISTRY,
NATIONAL BUREAUO F
STANDARDS]
Branched-chain Higher Sugars. I. A 9-Aldo-4-C-formyl-nonose Derivative BY ROBERT SCIIAFFER AND HORACE S. ISBELL RECEIVED SEPTEMBER 19, 1958 Two moleculcs of 5 - a ~ d o - ~ , 2 - ~ - i s o p r o p y ~ i d c n e - ~ - x ~ ~ f f - p e n t oinf ualkaline r a n o s e solution combine to form a branched-chain decose derivativc ( I ) by a n aldol condensation. An explanation is offered for the occurrence of this condensation, which is not a typical carbohydrate reaction. A proof of thc complete structure and configuration of I is presented and the compound is named 9-aldo-4-C-formyl-l,2 :S,9-di-O-isopropylidene-~-xylo-~-ido-nono-l,4 :9,G-difurano-4( 1),7-a-pyranose.
Introduction I n a Communication to the E d i t ~ rthe , ~ authors pointed out t h a t branched-chain aldoses containing S to 14 carbon atoms can be obtained in reasonably good yield by aldol condensation of suitable sugar derivatives. The present paper describes work establishing the structure of the branched-chain decose derivative I obtained from 5-aldo-I ,2-0isopropylidene-D-xvlo-pentofuranose (II)4.6 by treatment with alkali. The aldol condensation occurs with two-carbon and three-carbon hydroxy-aldehydes, hydroxyketones and 0-substituted hydroxy-aldehydcs.6 RIthough, prior to thc present work, a variety of sugars had been syiithesized by aldol condcnsations, the only products reported from tetroses or higher sugars are a heptulosc7 and a dodecitol.* (The latter was separated froin a n electrolyzed alkaline hexose mixture and its synthesis may be considered to have included an aldol condensation.) The aldol condensation involves two molecules, o w in the aldehyde form and the other in the enol (1) T h i s work was sponsored by t h e Division of Research. Atomic Energy Cummission. (2) Presented before t h e Division of C a r b o h y d r a t e Chemistry a t t h e
132nd Meeting of tli? American Chemical Society a t S e w York, N. Y., September 1 1 , 1957. (3) R . Scliaffrr i i i i i l I 1 S. Isbell, ?'HIS J O U R N A L . 8 0 , 7 5 0 (1958). (4) K. Iwarlare, 10
