Pyrazolo[3,4-b]pyridine compounds, and their use as phosphodiesterase inhibitors

• Main Authors: JULIE NICOLE HAMBLIN, ALISON JUDITH REDGRAVE, CHARLOTTE JANE MITCHELL, PAUL SPENCER JONES, ANTHONY WILLIAM JAMES COOPER, CHRISTOPHER DAVID EDLIN, MIKA KRISTIAN LINDVALL, MICHAEL DENNIS DOWLE, DIANE MARY COE, CAROLINE MARY COOK, MARTIN REDPATH JOHNSON, DAVID GEORGE ALLEN
• Format: Patent
• Language: English
• Published: 10.06.2010
• Subjects: CHEMISTRY; HETEROCYCLIC COMPOUNDS; HUMAN NECESSITIES; HYGIENE; MEDICAL OR VETERINARY SCIENCE; METALLURGY; ORGANIC CHEMISTRY; PREPARATIONS FOR MEDICAL, DENTAL, OR TOILET PURPOSES; SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS ORMEDICINAL PREPARATIONS

The invention relates to a compound of formula (I) or a salt thereof: wherein: R1 is C1-4alkyl, C1-3fluoroalkyl or -(CH2)2OH; R2 is a hydrogen atom (H), methyl or C1fluoroalkyl; R3a is a hydrogen atom (H) or C1-3alkyl; R3 is optionally substituted branched C3-6alkyl, optionally substituted C3-8cycloalkyl, optionally substituted mono-unsaturated-C5-7cycloalkenyl, optionally substituted phenyl, or an optionally substituted heterocyclic group of sub-formula (aa), (bb) or (cc): in which n1 and n2 independently are 1 or 2; and Y is O, S, SO2, or NR4; and wherein Het is of sub-formula (i), (ii), (iii), (iv) or (v): The compounds are phosphodiesterase (PDE) inhibitors, in particular PDE4 inhibitors. Also provided is the use of a compound of formula (I), or a pharmaceutically acceptable salt thereof, in the manufacture of a medicament for the treatment and/or prophylaxis of an inflammatory and/or allergic disease in a mammal such as a human, for example chronic obstructive pulmonary disease (COPD), asthma, or allergic rhinitis.