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survey has been made of the literature on the infrared spectroscopy of carbohydrates, in order to assemble and systematize information in this field. The Monograph discusses principles and instrumentation, sampling techniques, comparison of samples, and the interpretation of the spectra, particularly as regards functional groups of carbohydrates and their derivatives, correlations for the fingerprint region and beyond, and conformational studies. In addition, examples are discussed of the use of infrared spectra for qualitative and quantitative purposes and in the determination of structure. Special techniques are briefly described, including use of plane-polarized radiation, the technique of attenuated total reflection, and Raman spectra.

The co nform ation s of t wen ty-four aldopyranos id es h a ve been st udi ed by a nal ys is of t he ij· infra red absorpt ion spectra. The m ost stable co nform ations of t wel ve of t he glycos id es h ad p reviollsly been assig ned by R ee ves from a st ud y of t heir in stabilit y fa ctors; these conformations wer e aSS lim ed t o apply t o t he cr ystalline state, for whi ch t h e s pec tra h a d bee n recorded . The compounds were classifi ed in to (a) co nfi gurationally an d (b) structurally r elated .gro ups, a nd. t he spectra were in tercompared . The an alys is r evealed grou ps of absor pt lOll ba nds whi ch sh owed a co ncerted shift on chan ge of a nomeri c di spos it ion.Wi t h t hese groups of absorp tion bands t hus ident ifi ed , in tercompa ri son wit ll n ine of t he rem ain ing sp ectra afford ed evidence t hat t he a nomer ic group (1) Tlu·ee of t he glyeosides were ava il a bl e as t heir cr ystallin e complexes with calciu m chl oride. The spectra of t he e complexes were also exam in ed, a nd t he efTect of co-c rystalli zat io n with ca lciu m chlorid e is pointed out . I. Scope and Purpose of the ProjectThe sh ape or conformation of <1, molec ul e gret1.tly influ en ces its rfLtes of refLction fLnd othe r prop er ties. For this reaso n, detailed kn owledge of the co nforme1.-t ions of py nwoid derivfLtiv es is des irable. Our prior pu blir.ations on th is s u bj cct heLVe pres en ted fL system for nnmin g th e co nformat ions of pymnoid compounds [1,2].1 Th e con fo rmfLt ions of num er ous m eth yl glycosides and ot her p,rmnoid deriv;1.tiv es hav e b een determin ed by R eeves from (a) a studv of ster eomeri c fe1.cto rs and (b ) t he ty pe of com plex· formed in cuprHmmon ia solu tion. R eaction of c upnunmo nia with an aldopyranosid e m,1.Y somet imes CfLuse tlltemtion in the co nformation . H ence, e1.ssignments of conformation based on th e formation of copper complexes n eed confirm atioJl bv measuremen t of at least one relevant ph~Ts i cal cJl tll"acteristic.The work h er ein reported was primarily und ertaken to provid e infrared spectrograms of ald osides havin g the p~rmnoid rin g, wit h the obj ect of discovering correh1.tion s that migh t be of value in conformationa l a nalys is. Jt seemed possible that the axial 01' equa torial di sposition of refer ence groups in the various llJolecules of glycop~Tra nos id es should give rise to differ ent v ibrations, and that it should, accor d in gly, b e feasible to identify cer tain b a nds in their sp ectm as being ch aracter istic of t h e different ways of arrnnging t he refer ence groups. The infrared spectra for 11. group of aldopyranosid es have, th ere- Lhe table. 239 fore , b een recorded , ewd the b a nds h ave been compiled a nd then stud ied b\" statistic;1.1 a.nci comp~l,mti ve meth ods .Prior publica tion s from om laboratol".\' on rehted topics have dealt wi t h th e infrared a b orption sp ectrn of sugn,1" }1.Cete1 tes [3] a,nd of some cycli c a ce tals of s ug,(1" [4], e1.nd with a s.\'s tem fo r classif.vin g ...

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The infr ared absorption spcctra of t wenty-eigh t I-methoxycth y lidene and isopropylidene acetals of sugars have been record ed and analyzed. The formulas of t he compounds were gro uped according to structure, a nd t he absorp tion bands for each group were considered in relation to t h e bands found for t he other stru cturally related compounds. No bands were found for t he unequivocal d etection of t he 1,3-c1ioxola ne r ing attached respectiv ely to an aldopentofuranose or a ketopentofuranose, an aldopentopyranose, an wld ohexofuranose, an aldohexopyranose or a ketohexopyranose, a Ul'onic a cid salt or lactone, a sugar :,lcohol, or a sugar keto-acid salt. R egardless of t he fin e structure of t he dioxolane compounds, certain strong band s were observed, but t he bands a re not. easily recognized from an inspection of one or t wo spectra and a re not characteristic of t hese compound only.