[1-(3-Oxo-2-aza-spiro[4,5]dec-2-ylmethyl)cyclohexyl]acetic Acid;Gabapentin Related Compound D;Gabapentin Related Compound D (10 mg) ((1-(3-oxo-2-aza-spiro[4.5]dec-2-ylmethyl)-cyclohexyl)acetic acid);1-[(3-oxo-2-azaspiro[4.5]dec-2-yl)Methyl]cyclohexaneacetic Acid;Gabapentin USP RC D;Gabapentin Related Material D;Gabapentin impurity D;Gabapentin impurity D (EP)