Coumarins I

Coumarins IV

“…The gemdimethyl character of the compound at the 2'position is evident from the pair of three-proton singlets at T 8.55 and 8.57. With very minor differences, this spectrum was identical with that of pteryxin (111), the known cis-3'-acetoxy-4'-angeloyloxy-3',4'-dihydroseselin (4). Thus, the weight of evidence indicates that IV is the correct structure.…”

Bisabolane-Type Sesquiterpenes: Liginvolones A−D from Ligusticum involucratum

“…The molecular formula was determined as C 20 H 28 O 5 These data were similar to those of bisabolangelone (6), 7-10 one of the sesquiterpenes from Angelica silvestis L., except for the presence of an isovaleryl spin system [δ 2.23 (1H, dd, J ) 15.0, 7.2 Hz), 2.15 (1H, dd, J ) 15.0, 7.0 Hz), 2.05 (1H, ddqq, J ) 7.2, 7.0, 6.6, 6.6 Hz), 0.95 (6H, d, J ) 6.6 Hz)] instead of a C-9 methine signal [δ 2.65 (1H, d, J ) 6.9 Hz)] in 6.…”

Solid-Phase Parallel Synthesis of Drug-Like Artificial 2H-Benzopyran Libraries

“…Among biologically active heterocyclic scaffolds, the well-known privileged benzopyran structure frequently appears in many natural products and artificial bioactive molecules, that exhibit a wide range of biological activities [16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49]. Representative examples of benzopyran-containing natural products and artificial bioactive molecules are illustrated in Figure 1.…”