189579-19-9Relevant academic research and scientific papers
Strategies for ansamycin antibiotics. Asymmetric synthesis of the C(3)- C(21) subunit of herbimycin A
Martin, Stephen F.,Limberakis, Chris,Burgess, Laurence E.,Hartmann, Michael
, p. 3561 - 3572 (2007/10/03)
The asymmetric synthesis of 25, which constitutes the C(3)-C(21) segment of the stereochemically complex ansa chain of herbimycin A (2) has been achieved. The approach features the furan-hydropyran transformations 7→5 and 8→6 and the fragment coupling of 5 and 6 to produce the trisubstituted alkene 4 with high stereoselectivity. Stereoselective addition of the aryl anion derived from 24, which possesses the novel BIPSOP protecting group for the primary amine function, to the lactol 22 then delivered 25 as the major product.
Diprotection of primary amines as N-substituted-2,5-bis[(triisopropylsilyl)oxy]pyrroles (BIPSOP)
Martin, Stephen F.,Limberakis, Chris
, p. 2617 - 2620 (2007/10/03)
Primary amines are diprotected as their 2,5-bis[(triisopropylsilyl)oxy]pyrrole derivatives (BIPSOP). This protecting group is stable to strong bases such as organolithiums and alkoxides at 0°C and to temperatures up to about 150°C. Removal may be accomplished by a mild two step sequence.
