1. a Department of Chemistry , The University of Alabama at Birmingham , Birmingham, Alabama, 35294, U.S.A.
2. b Southern Regional Research Center , U.S. Department of Agriculture , P.O. Box 19687, New Orleans, LA, 70179, U.S.A.
3. c Department of Chemistry , Indiana University of Pennsylvania , Indiana, Pennsylvania, 15705–1087, U.S.A.
4. d Shafizadeh Rocky Mountain Center for Wood and Carbohydrate Chemistry , The University of Montana , Missoula, Montana, 59812, U.S.A.