Ghostbusters franchise, which includes a 1989 sequel, "Ghostbusters II", two animated television series, "The Real Ghostbusters" and "Extreme Ghostbusters", several video games, and a 2016 reboot film. Peter Venkman, Raymond Stantz, and Egon Spengler are scientists investigating the paranormal at Columbia University. After they lose their jobs following a botched ghost investigation in the University library, they establish Ghostbusters, a paranormal investigation and elimination service. They open their business in a disused firehouse and develop high-tech equipment to capture ghosts. On their first call, at a hotel, Egon warns the group never to cross the energy streams of their proton pack
Pictet–Spengler reaction tetrahydroisoquinoline synthesis. Reaction conditions are generally harsher than the indole variant, and require refluxing conditions with strong acids like hydrochloric acid, trifluoroacetic acid or superacids. Instead of catalyzing the Pictet-Spengler cyclization with strong acid, one can acylate the iminium ion forming the intermediate "N"-acyliminium ion. The "N"-acyliminium ion is a very powerful electrophile and most aromatic ring systems will cyclize under mild conditions with good yields. Tadalafil is synthesized via the "N"-acyliminium Pictet–Spengler reaction. This reaction can also be catalyzed by AuCl and AgOTf. When the Pictet–Spengler reaction is performed with an aldehyde other than formaldehyde, a new chiral center