Egon Spengler exhausting trek up the stairs of 55 Central Park West. While in the alternate dimension of the library, Egon is heard to groan, "Oh no," and when Ray asks if he saw something scary, Egon replies, "Stairs, lots of stairs". Before the "Return to Sedgewick Hotel" mission, Stantz comments that Spengler was once a coroner, to which he replied that he maintains interest in the subject as a hobby. Spengler appears in Beeline's "Ghostbusters" game for iOS alongside his niece, Michelle Ying. The game was released on January 24, 2013. Spengler appears in "Lego Dimensions", with archival audio of Harold
Pictet–Spengler reaction hydrochloric acid forming a tetrahydroisoquinoline. Like the Mannich reaction, aldehydes give good yields while ketones tend to give lower conversion. The Pictet–Spengler reaction has been applied to solid-phase combinatorial chemistry with great success. An analogous reaction with an aryl-β-ethanol is called Oxa-Pictet–Spengler reaction The reaction mechanism occurs by initial formation of an iminium ion (2) followed by electrophilic addition at the 3-position, in accordance with the expected nucleophilicity of indoles, to give the spirocycle 3. After migration of the best migrating group, deprotonation gives the product (5). Replacing an indole with a 3,4-dimethoxyphenyl group give the reaction named the Pictet–Spengler