3,5-Dihydro-pyridazino[4,5-b]indol-4-one and 2,5-dihydro-pyridazino[4,5-b]indol-1-one derivatives

Disclosed are 3,5-dihydro-pyridazino[4,5-b]indol-4-one and 2,5-dihydro-pyridazino[4,5-b]indol-1-one derivatives as represented by the general formula (II), wherein ring F is as represented by the formula (X) or (X'), and wherein the remaining substituents are as defined herein. Further disclosed is a pharmaceutical composition which comprises a compound as defined above and a pharmaceutically acceptable carrier for the inhibition of the Vascular Endothelial Growth Factor Receptor (VEGFR) and for the treatment of conditions such as angiogenic disorders (including cancer of solid tumors) endometriosis diabetic retinopathy psoriasis hemangioblastoma Alzheimer's disease motor neuron disorders (e.g. amyotrophic lateral sclerosis) Parkinson's disease cerebrovascular disorders (e.g., stroke, ischaemia) Huntington's disease AIDS dementia epilepsy multiple sclerosis peripheral neuropathies (e.g., those affecting DRG neurons in chemotherapy associated peripheral neuropathy) including diabetic neuropathy disorders induced by excitatory amino acids and disorders associated with concussive or penetrating injuries of the brain or spinal cord.