Search results for "Sulfuryl chloride"
showing 2 items of 2 documents
Chemoenzymatische „Chiral-Pool”-Synthese von (+)-exo-Brevicomin aus Kohlenhydraten mit Fructose-1,6-diphosphat-Aldolase
1990
Chemoenzymatic “Chiral-Pool” Synthesis of (+)-exo-Brevicomin from Carbohydrates Using Fructose 1,6-Diphosphate Aldolase Fructose-1,6-diphosphate aldolase (EC 4.1.2.13) catalyzes the stereospecific aldol reaction between 1,3-dihydroxyacetone phosphate (4) and 5-oxohexanal (3) or its 5-dithiane-protected analog 8. The products of the aldol reactions are dephosphorylated with acid phosphatase (EC 3.1.3.2). Whereas the aldol adduct of 3 cyclizes spontaneously to give the bicyclic brevicomin precursor 3, the adduct of 8 first has to be deprotected with sulfuryl chloride and wet silica gel. The resulting bicyclic α-hydroxy ketone 3 is reduced with LiAlH4 to form the 1,2-diol 14 which is then deox…
Synthesis and Conformational Analysis of Tetrahydroisoquinoline-Fused 1,3,2-Oxazaphospholidines and 1,2,3-Oxathiazolidines
2008
The cyclizations of tetrahydroisoquinoline 1,2-amino alcohols with phenylphosphonic dichloride, bis(2-chloroethyl)phosphoramidic dichloride, thionyl chloride and sulfuryl chloride were utilized to synthesize 1,5,6,10b-tetrahydro-1,3,2-oxazaphospholo[4,3-a]isoquinolines (2, 3), 1,5,10,10a-tetrahydro-1,3,2-oxazaphospholo[3,4-b]isoquinolines (8, 9), 1,5,6,10b-tetrahydro-1,2,3-oxathiazolo[4,3-a]isoquinolines (4–6) anda 1,5,10,10a-tetrahydro-1,2,3-oxathiazolo[3,4-b]isoquinoline (11), which are the first representatives of these ring systems. NMR spectroscopic analysis revealed the existence of conformational equilibria that are fast on the NMR timescale. Theoretical DFT calculations pointed to t…