Egon Spengler a bronze bust of Harold Ramis as the film's version of Spengler is seen just as Erin Gilbert leaves her office. During the credits of "Ghostbusters", the words "For Harold Ramis" are seen. Spengler's hair was changed from brown in the films (Ramis' natural hair color) to a blond pompadour in the animated series (Spengler wore his hair in a ponytail on "Extreme Ghostbusters"). This was reportedly done due to legal issues concerning character / actor likenesses. Despite his leanings toward science, Spengler has a family history of witchcraft (three ancestors, Zedekiah, Eli and Ezekiel, were wizards), of which he
Pictet–Spengler reaction is created. Several substrate- or auxiliary-controlled diastereoselective Pictet–Spengler reactions have been developed. Additionally, List "et al." have published a chiral Brønsted acid that catalyzes asymmetric Pictet–Spengler reactions. Tryptophans: diastereocontrolled reaction The reaction of enantiopure tryptophan or its short-chain alkylesters leads to 1,2,3,4-tetrahydro-"β"-carbolines in which a new chiral center at C-1 adopts either a "cis" or "trans" configuration towards the C-3 carboxyl group. The "cis" conduction is kinetically controlled, i.e. it is performed at lower temperatures. At higher temperatures the reaction becomes reversible and usually favours racemisation. 1,3-"trans" dominated products can be obtained with "N"-benzylated tryptophans, which are accessible by reductive