Synthesis of virgatol and virgatenol, two naturally occurring coumarins from Pterocaulon virgatum (L.) DC, and 7-(2, 3-epoxy-3-methylbutoxy)-6-methoxycoumarin, …
Abstract The synthesis of a number of naturally occurring coumarins from Pterocaulon virgatum (L.) and Conyza obscura DC is described for the first time. It concerns the synthesis of 7-(2-hydroxy-3-methoxy-3-methylbutoxy)-6-methoxycoumarin (virgatol, 1), 7-(2-hydroxy-3- methyl-3-butenyloxy)-6-methoxycoumarin (virgatenol, 2) and 7-(2, 3-epoxy-3-methylbutoxy)- 6-methoxycoumarin (3). In addition, a straightforward synthesis of scopoletin (4)(7-hydroxy ...