Bromocyclization of AlkynylGuanidine: A New Approach to the Synthesis of Cyclic Guanidinesof Saxitoxin

  title={Bromocyclization of AlkynylGuanidine: A New Approach to the Synthesis of Cyclic Guanidinesof Saxitoxin},
  author={Yusuke Sawayama and Toshio Nishikawa},
Bromocyclization of propargyl and homopropargyl guanidines possessing homopropargyl alcohol provides five- and six-membered cyclic guanidines with spiro-hemiaminal, respectively, a candidate of precursors for saxitoxin. 
5 Citations
Halocyclization of Unsaturated Guanidines Mediated by Koser's Reagent and Lithium Halides.
The synthesis of halogenated cyclic guanidines through iodine(III)-mediated umpolung of halide salts is described and their regioselectivities are described.
A Synthetic Strategy for Saxitoxin Skeleton by a Cascade Bromocyclization: Total Synthesis of (+)-Decarbamoyl-α-saxitoxinol.
A new synthetic strategy for the formation of the ABC tricyclic framework of saxitoxin was developed, which enables the concise stereocontrolled total synthesis of (+)-decarbamoyl-α-saxitoxinol, which is a naturally occurring saxit toxin analogue.
Synthesis of Saxitoxin and Its Derivatives.
Two consecutive carbon-nitrogen bonds at C-5 and C-6 in saxitoxin were effectively installed by the sequential Overman rearrangement of an allylic vicinal diol derived from d-malic acid.
Synthesis of Dibromo Compounds Containing 2,6-Dioxabicyclo[3.1.1]heptane Similar to Core Moiety of Thromboxane A2
Thromboxane A2, a potent platelet aggregation factor, contains a labile 2,6-dioxabicyclo[3.1.1]heptane as the core moiety. Dibromo compounds with a similar core structure were synthesized by the