[1]JournalofHeterocyclicChemistry,1989,vol.26,p.687-692
[2]TetrahedronLetters,1986,vol.27,p.3127-3132
[1]JournalofHeterocyclicChemistry,1989,vol.26,p.687-692
[2]TetrahedronLetters,1986,vol.27,p.3127-3132
[1]TetrahedronLetters,1986,vol.27,p.3127-3132
[2]JournalofHeterocyclicChemistry,1989,vol.26,p.687-692