SRCTIONAL TRANSACTIONS.— B. 357 



SECTION B.-CHEMISTRY. 



(l''or references to the publication elsewhere of communications entered in the 

 following list of transactions, sec p. 408.) 



Thursday, September 7. 



1. Presidential Address by Principal J. C. Irvine, F.R.S. 



(Seep. 25.) 



2. Di"- Helen S. Gilchrist. — The Preparation and Constitution of 



Sunihclic Fats containing a Carbohydrate Cliain. 



The products obtained when a carbohydrate chain is coupled with the 

 unsaturated groups characteristic of natural fats have been studied with the 

 object of establishing the constitution of the synthetic fats thus obtained. 



As shown by Lapworth and Pearson, o-methylglucoside and mannitol both 

 combine, on heating in the presence of sodium ethoxide, with the oleyl residues 

 of olive oil, thereby liberating glycerol. 



The present research has proved that in the first case a mono-oleate is initially 

 formed, whilst in the second two oleyl groups enter the hexitol chain. This 

 condensation is immediately followed by internal dehydration, the carbohydrate 

 chain, in each case, losing one molecule of water, the fatty residues remaining 

 intact. 



Anhydro-methylglucosida mono-oleate and mannitan di-oleates are definite 

 chemical individuals. On methylation they yield monomethyl derivatives, 

 which, however, are unstable even in the high vacuum of the Gaede pump. On 

 being heated with acid alcohol these methylated compounds each give methyl 

 oleate, together with an alkylated sugar derivative. In both cases the anhydro- 

 ring in the molecule persists during hydrolysis, and thus a passage is opened 

 into the series of anhydro-sugar derivatives and alcohols. 



Examination of the above cleavage products confirms the views already held 

 regarding the mechanism of the reactions discussed, and complete structural 

 formulae are assigned to the original ' methylglucoside ' and 'mannitol fats.' 



3. Mr. John Pryde. — A New Type of Nitrogenous Sugar Derivative. 

 In extending his studies on the action of sodium hypochlorite on amides 



of a-hydroxy acids Weerman applied his reaction to the amides of simple 

 hexonic acids, and so deviised what has proved to be the best practical method 

 of degrading hexoses to pentoses. 



In the present communication the results of applying this degradation method 

 to a fully methylated hexose were given. The investigation was originally under- 

 taken in the hope that a propylene-oxide form of a methylated arabinose would 

 be obtained in place of the normal butylene-oxide type, or alternatively that 

 the intermediate compounds would be isolated and thus elucidate the course 

 of the reaction as applied to the sugar group. 



Tetramethylglucose was oxidised to tetramethylgluconic acid, which was 

 isolated as its internal lactone. The lactone, dissolved in absolute alcohol, was 

 treated with dry ammonia and the amide was isolated in a crystalline condition. 

 Evidence is available to show that, this compound does not possess the structure 

 of a true acid amide, but exists in the form of an amino-lactone. On subjecting 

 the amide to the action of cold alkaline hypochlorite a crystalline body of the 

 composition of the intermediate isocyanate was obtained, and from its behaviour 

 the constitution of an internal urethane has been assigned to it. The reaction 

 proceeds as follow's : — 



yNH,, 



C<' ' CONHo N = C = yCHOMe^ 



yinole c'nOMe c'HOMe ^^OMe NH 



\ CHOJIe ~^ CHOMe ~^ CHOMe "^ /"^^ ^° 



/ 



\o/ 



^CH CHOH CHOH 



