Yuhpyng Chen - New York NY,
Arthur Nagel - New York NY,
514/249000, 514/258000, 514/266000, 514/303000, 514/321000, 514/322000, 540/001000, 544/277000, 544/350000, 546/118000, 546/198000, 546/119000
Compounds of the formula
wherein ring A, ring B, ring D, R, R, R, R, R,R, R, R, E, G, X and P are as defined below. The compounds of formula I are cholinesterase inhibitors and are useful in enhancing memory in patients suffering from dementia and Alzheimer's disease.