CONSTITUTION OF THE SUGAR SERIES. 



1 



167 



Decose is at present unknown. 



Cane sugar I represent by means of two hexagons minus a 

 molecule of water thus : — 



H HO 



HO 



HO 



H' N HO HO' H 



the inversion of cane sugar by hydrolysis, — ■ 



C 12 H 22 1X + OH 2 = 2C 6 H 12 6 

 may be regarded as complete saturation of the compound. 



It remains to add that the optical isomeric hexoses may be well 

 represented by placing the hydrogen atoms in the direction of the 

 hands of a clock to show the dextro-rotatory position and in the 

 reverse direction for the lsevo-rotatory effect ; and equal combin- 

 ation of the two explaining the optically inactive sugars. 



The series may be stated as follows : — ■ 



(General formula C n H 2n O n ) 



Monose . 



. C 



H 2 



Hexose . 



.. C 6 H la 6 



Biose 



. c 2 



H 4 2 



Heptose. 



.. C 7 H 14 7 



Triose 



. c 3 



H 6 3 



Octose . 



• ^8 Hi 6^8 



Tetrose . 



. c 4 



H 8 0, 



ISTonose . 



: C 9 H 18 9 



Pentose 



.. c 5 



H 10 5 



Decose . 



.. \J i o -H-20 ^10 



