1-Oxa-3-azaspiro(4,5)decane-2,4-dione, 7-methyl-3-(2-(4-pyridyl)ethyl)-, high melting isomer 7-Methyl-3-(2-(4-pyridyl)ethyl)-1-oxa-3-azaspiro(4,5)decane-2,4-dione high melting isomer RN7060267