Synthesis of pyrrolo[2,3-d][1,2,3]thiadiazole-6-carboxylates via the Hurd-Mori reaction. Investigating the effect of the N-protecting group on the cyclization.
A route to methyl pyrrolo[2,3-d][1,2,3]thiadiazole-6-carboxylates as potential plant activators and inducers of systemic acquired resistance (SAR) is reported. A synthetic strategy based on cyclization of the thiadiazole ring system utilizing thionyl chloride via the Hurd-Mori protocol as key step was developed. Success of the ring closure reaction turned out to be highly dependent on the nature of the N-protecting group of the pyrrolidine precursor. While electron donors such as alkyl gave only poor conversion to the required 1,2,3-thiadiazoles, an electron withdrawing substituent such as methyl carbamate gave superior yields.
Stanetty
Peter
P
Vienna University of Technology, Institute of Applied Synthetic Chemistry, Austria. peter.stanetty@tuwien.ac.at
Turner
Martin
M
Mihovilovic
Marko D
MD
D002625:Chemistry, Organic / Q000379:methods*; D003500:Cyclization; D007113:Immunity, Innate / Q000187:drug effects; D008954:Models, Biological; D009584:Nitrogen / Q000737:chemistry*; D010944:Plants / Q000187:drug effects / Q000276:immunology; D011758:Pyrroles / Q000138:chemical synthesis* / Q000737:chemistry; D013830:Thiadiazoles / Q000138:chemical synthesis* / Q000737:chemistry
D011758:Pyrroles; D013830:Thiadiazoles; D009584:Nitrogen