Concepts in organic synthesis: Retrosynthesis, disconnection, synthons, linear and convergent synthesis, umpolung of reactivity and protecting groups.
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1.The major product formed in the following reaction is
The reagent H2, 10% Pd/C, EtOH, deprotect the ‘Bn’ and Cbz in amino acid.
2.The major product formed in the following reaction is….
Ring opening takes place from axial attack of H– at position (2)
3.The major product formed in the following reaction sequence is
4.The major products A and B in the following reaction sequence are
5.Structures of the intermediate A and the major product B in the following reaction sequence are
6.The products A and B in the following reaction sequence are
The first step is the conversion of (5R)-5-hydroxy-L-lysine to methyl ester by treatment with TMSCl in methanol. The critical lactam formation was effected by a unique cooperative acid-conjugate base catalysis resulting from the base triethylamine and HCl (from TMSCL)
In the subsequent step O – Acylation takes place preferentially.