ANTIBIOTICS 



181 



optically active substance, methyl streptubiosaminicle 

 dimethylacetal hydrochloride, in solution : — 



QlH37-39^70l2.3HCl + 3 CH3OH 



(iStreptomycin hjTli-ochloride) 



C8Hi8X604-2HCl + H2O + 

 (Streptidine) 

 Ci3H2o-22NO,(OCH3)3.Hri 

 (Streptobiosaminide dimethyl acetal) 



On hydrolysis streptidine loses ammonia and carbon 

 dioxide and forms a new base, streptamine : — 



The six nitrogen atoms of streptidine are present as two 

 mono -substituted guanidine groups which are replaced 

 by two amino groups in streptamine. The oxygen atoms 

 are present as hydroxyl groups since acetyl and benzoyl 

 derivatives can be obtained. Stre^^t amine is veiy pro- 

 bably a diamino totrahydroxy c^^lohexane with the 

 amino groujjs at positions 1:3 or 1:4: — 



NH.R 



I 

 CH 



CHOH CHOH 



I I 



CHOH CHOH 



CH 



I 

 NH.R 



Streptamine, R = H. 



NH.R 



I 

 CH 



CHOH CHOH 



I I 



CHOH CN.NH.R 



\ / 



CH 



OH 



iStreiDtidiue, R = — C 



XH 



XH, 



Methyl streptobiosaminide dimethyl acetal is most 

 probably derived by the action of methanol on a nitrogen 

 containing disaccharide, streptobiosamine. The nitrogen 

 atom is not present as an amino group but probably as 

 a methylamino group attached at position 2 of one of 

 the hexose luiits. 



