title: Total synthesis of polyamine toxin HO-416b and Agel-489 using a 2-nitrobenzenesulfonamide strategy.
abstract: Total synthesis of spider toxins HO-416b (1) and Agel-489 (2) was accomplished using the 2-nitrobenzenesulfonamide (Ns) group as both a protecting and activating group. In this strategy, the C-N bonds were constructed by alkylation of sulfonamides with alkyl halides or Mitsunobu reaction with the corresponding alcohol. Beginning with monoprotection of the symmetrical diamine, the construction of the backbone from diamine 3 was efficiently accomplished in 7 steps for 14 and 9 steps for 29. Removal of the Ns group while the substrate was attached to a novel solid support enabled the efficient isolation of this highly polar compound.
authors.affiliation: Graduate School of Pharmaceutical Sciences, University of Tokyo CREST, The Japan Science and Technology Corporation.
authors.forename: Y
authors.initials: Y
authors.lastname: Hidai
authors.forename: T
authors.initials: T
authors.lastname: Kan
authors.forename: T
authors.initials: T
authors.lastname: Fukuyama
mesh_terms: D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009574:Nitro Compounds / Q000737:chemistry*; D011073:Polyamines / Q000138:chemical synthesis* / Q000737:chemistry; D013057:Spectrum Analysis; D013111:Spider Venoms / Q000737:chemistry*; D013449:Sulfonamides / Q000737:chemistry*
chemical_list: C419451:Agel-489; C410205:HO 416b; D007211:Indoles; D009574:Nitro Compounds; D011073:Polyamines; D013111:Spider Venoms; D013449:Sulfonamides