Hydrogen-bonded chains of rings in 3-tert-butyl-1-phenyl-7-(4-trifluoro- methyl-benz-yl)-4,5,6,7-tetra-hydro-1H-pyrazolo[3,4-b]pyridine-5-spiro-1′- cyclo-hexane-2′,6′-dione and 3-tert-butyl-7-(4-methoxy-benz-yl)-1- phenyl-4,5,6,7-tetra-hydro-1H-pyrazolo[3,4-b]pyridine-5-spiro-1′-cyclo- hexane-2′,6′-dione

1. Trilleras, J.
2. Cruz, S.
3. Cobo, J.
4. Low, J.N.
5. Glidewell, C.