2'-(tert-Butoxycarbonyl)-3',4'-dihydro-2'H-spiro[oxetane-3,1'-pyrrolo[1,2-a]pyrazine]-6'-carboxylic acid 1g

2'-(tert-Butoxycarbonyl)-3',4'-dihydro-2'H-spiro[oxetane-3,1'-pyrrolo[1,2-a]pyrazine]-6'-carboxylic acid 1g