(2R,4R)-2,4-dimethylcyclopentanone InChI=1/C7H12O/c1-5-3-6(2)7(8)4-5/h5-6H,3-4H2,1-2H3/t5-,6-/m1/s cyclopentanone, 2,4-dimethyl-, (2R,4R)-