Addition reactions of heterocyclic compounds. Part LI. Cyclobuta-[b]pyridines from reactions of dimethyl acetylenedicarboxylate with 1-alkyl-1,4-dihydropyridines and the cycloelimination of amide and carboxy-groups
1972 ◽
pp. 2918
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1975 ◽
pp. 394
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1979 ◽
pp. 2171
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