Synthesis of certain spiro Heterocyclic compounds of possible Pharmacological Activity

In the search of chemical and pharmacodynamio pro- pertils of 2-alkyl -4- oyano-3- imino -1-thio -5,6,7,8-tetra- hydro- 1h,9H-pyrimido [1,6-a] azepines (I-iv), several ohmical transformations were carried out on these bridge –head . nitrogen, bcyclic , compounds.Akyation of the 3-imino group was effected with diakyl sulphates, yielding the 3-alky imonium alkylsulphates (V-ViI).the aqueous solutions of their corresponding 3-alkylimoum akyl sulphats ,by the action of sodium hydroxide.Reduction of (i-iV) with sodium borohydride was found to give , excusively , the o-aminonitrile compounds 2-alkyl-3- amino [1,6-a] azepines (xiii-xvi) , rather than the 3-imino derivative © , in spite of that the acid hydro- ysis afforded the 3-oxo derivatives (xvii-xix). The structre of the conjugated o- aminonitrie compounds (A but not B) was confirmed by i.r. and n.m.r. spectral date (lov frequency or the cyano group in the i.r. spectrum, and the protons of the conjugated primary amino group apeararing at 4.78 in the n.m.r. spectrum).