title: 5-(Methylthio)tetrazoles as Versatile Synthons in the Stereoselective Synthesis of Polycyclic Pyrazolines via Photoinduced Intramolecular Nitrile Imine-Alkene 1,3-Dipolar Cycloaddition.
abstract: A key thioether substituent in readily accessible 2-alkyl-5-(methylthio)tetrazoles enables facile photoinduced denitrogenation and intramolecular nitrile imine 1,3-dipolar cycloaddition to afford a wide range of polycyclic pyrazoline products with excellent diastereoselectivity. The methylthio group red-shifts the UV absorbance of the tetrazole, obviating the requirement in all previous substrate systems for at least one aryl substituent, and can subsequently be converted into a variety of other functionalities. This synthetic platform has been applied to the concise total syntheses of the alkaloid natural products (±)-newbouldine and withasomnine.
authors.affiliation: Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065, United States.
authors.forename: Daniel
authors.initials: D
authors.lastname: Pla
authors.affiliation: Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065, United States ; Tri-Institutional Research Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065, United States.
authors.forename: Derek S
authors.initials: DS
authors.lastname: Tan
authors.affiliation: Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065, United States ; Tri-Institutional Research Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065, United States.
authors.forename: David Y
authors.initials: DY
authors.lastname: Gin
references.citation: J Am Chem Soc. 2007 Dec 26;129(51):15734-5
references.pmid: 18047333
references.citation: ACS Chem Biol. 2010 Sep 17;5(9):875-85
references.pmid: 20666508
references.citation: Planta Med. 1998 Feb;64(1):90-1
references.pmid: 9491772
references.citation: Org Lett. 2007 Oct 11;9(21):4155-8
references.pmid: 17867694
references.citation: Angew Chem Int Ed Engl. 2009;48(13):2276-86
references.pmid: 19067446
references.citation: Org Biomol Chem. 2009 Oct 7;7(19):4052-6
references.pmid: 19763310
references.citation: Acc Chem Res. 2011 Sep 20;44(9):828-39
references.pmid: 21609129
references.citation: Pharmazie. 1969 Jul;24(7):382-4
references.pmid: 5810243
references.citation: Angew Chem Int Ed Engl. 2010;49(3):577-80
references.pmid: 20013833
references.citation: Org Lett. 2009 Aug 20;11(16):3570-3
references.pmid: 19637915
references.citation: Phys Chem Chem Phys. 2010 Nov 7;12(41):13603-15
references.pmid: 20852799
references.citation: Tetrahedron Lett. 1968 Nov;(54):5711-4
references.pmid: 5697174
references.citation: J Am Chem Soc. 2011 Aug 10;133(31):11912-5
references.pmid: 21736329
references.citation: Recent Pat Antiinfect Drug Discov. 2009 Nov;4(3):154-63
references.pmid: 19545230
references.citation: J Am Chem Soc. 2009 Jul 1;131(25):8740-1
references.pmid: 19505097
references.citation: Org Lett. 2011 Aug 5;13(15):4016-9
references.pmid: 21744785
references.citation: Tetrahedron Lett. 1968 Nov;(54):5707-10
references.pmid: 5697173
references.citation: J Am Chem Soc. 2006 Oct 11;128(40):13255-60
references.pmid: 17017806
references.citation: J Org Chem. 1996 Jun 14;61(12):4115-4119
references.pmid: 11667291
references.citation: J Am Chem Soc. 2010 Oct 27;132(42):14812-8
references.pmid: 20919707
references.citation: Mini Rev Med Chem. 2011 Aug;11(9):771-821
references.pmid: 21651464
references.citation: J Am Chem Soc. 2010 Jun 9;132(22):7631-7
references.pmid: 20481497
references.citation: Chem Rev. 2001 Oct;101(10):3219-32
references.pmid: 11710070
references.citation: Org Lett. 2012 Jan 6;14(1):256-9
references.pmid: 22145621