Question

Naproxen belonds to a class of pharmaceuticals referred to as non-steroidal anti-inflammatorydrugs or NSAIDS. FOr Naproxen (S)-(+) enatinomer is the desired pharmacological activite while the (R)-(-) enatinomer is potentially a liver toxin. Due to this, commerical Naproxen is sold as the (S)-(+) with high levels of optical purity. Calculate the observed rotation, a for naproxen from the following info& show work: %S=90% [a] literature= +66.0 concentration = 20g/78mL path length=2dm

Answer 1

specific rotation = observed rotation / concentration x length

specific rotation = + 66.0

concentration = 20g/78 ml = 0.256 g/ml

path length = 2 dm

observed rotation = specific rotation x concentration x length

                          = 66 x 0.256 x 2

observed rotation = 33.8^o