摘要: Bears Ears National Monument in Utah boasts stretches of red-and-yellow sandstone so brilliant they appear to be ablaze and rock structures so precarious they appear to defy gravity. The rugged terrain south of the Colorado River also has reserves of oil and natural gas that are currently...
NEW MATERIAL:The compound of formula I {R<1> is alkyl or tolyl; R<2> is H, OH, alkoxy or alkyl; R<3> is H, alkyl, alkenyl or cycloalkylalkyl; X is CO, CH2 or C(OH)H; g is 1 or 2; h is 2 or 3; Y is H, alkyl, CN, CH2COOR (R is H, alkyl, group of formula...