Synthesis and Characterization of 8-(4-Dimethyl amino-phenyl)-9-(6~R-benzothiazol-2-yl)-7-oxa-9-aza-spiro[4.5]decane-6,10-dioneand 8-(2- hydroxy-phenyI)-9~(6-R-benzothiazol-2-yl)-7-oxa-9-azaspiro[ 4,5]decane-6,10- dione by reaction of 2-Oxa-spiro[3.4]octanl, 3-dionewith(4-DimethyIamino-benzylidene)-(6-R-benzothiazoI- 2-yl)-amine and 2-[(6-R-benzothiazol-2- yIimino)-methyl]-phenoL

(4-Dimethyiamino -benzylidene)-(6-R-benzothiazol-2-yl)-amine and 2-[(6-Rbenzothiazol- 2-ylimino)-methyl]-phenol (Schiff bases) were prepared by condensation of 6- R-2-amino benzothiazol with Salicylaldehyde and 4-dimethyl amino benzaldhyde. These Schiff bases were reacted with 2-Oxa-spiro[3.4] octane-1,3-dione by heating with reflux in dry benzene at 80c for 3hrs.togive a six-member heterocyclic ring system;8-(4- Dimethylamino-phenyl)-9-(-6-R-benzothiazol-2-yl)-7-oxa-9- spiro[4.5] decane-6,10-diones and 8-(2-hydroxy-phenyl)-9-(6-R-benzothiazol 2-yl)-7-oxa-9- spiro[4.5]decane- 6,10diones.Thesecompounds react with pyrrolidine to give 1 -(Pyrrolidine-1 -carbonyl)- cyclopentanecarboxylicacid(4-dimethylamino-phenyI)-hydroxyl-methyl-(6-benzothiazol-2- yl)-amide and 1 -(Pyrrolidine-1-carbonyl)-cyclopentane carboxilic acid [2-hydroxy-(2- hydroxyl-phenyI)-methyl]-(6-R-benzothiazoI-2-yl)-amide.The final products were identified by their m.ps, elemental analyses,IR, and UV-Visible spectra.