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 imine generated from the condensation of the aldehyde and amine. This helps to explain the need for an acidic medium in some substrates, as the imine may not be electrophilic enough for ring closure to occur but the Iminium ion is capable of undergoing the reaction. The Pictet-Spengler reaction is widespread in both human industry and biosynthesis. It has remained an important reaction in the fields of alkaloid and pharmaceutical synthesis since its inception, where it has been employed in the development of many beta-carbolines. The enzyme strictosidine synthase is an example of nature utilizing the Pictet-Spengler reaction, which generates