The synthesis of (±)-mesembrine

Polyether carboxylic acids incorporating a benzodioxinic subunit: synthesis and complexing ability of sodium and potassium

“…However, Swern oxidation (14) of 8 and 12 gave aldehydes 9 and 13, which were then subjected to alkaline oxidation with silver nitrate (15) to afford the required acid derivatives 2 and 3.…”

“…Formation of 2-ligand-1-cation complexes, i.e., A2H2M' or A,M-, is improbable here since good fits were obtained assuming formation of only AHM+ and AM. Acid dissociation constants of the AHM+ species in columns 2 and 3 of Table I For comparison, previous data (1 [6][7][8][9][10][11][12][13][14][15][16][17][18] for naturally occurring carboxylic polyether ionophores are given in Table 1. Also, some pK, values of simple carboxylic acids obtained under the conditions described here are given in Table 2.…”

Isolation and Structure of Eucosterol and 16 β‐Hydroxyeucosterol, Two Novel Spirocyclic Nortriterpenes, and of a New 24‐ Nor‐5α‐chola‐8, 16‐diene‐23‐oic Acid from Bulbs of Several Eucomis Species

“…The biosynthesis of the ether linkage has been established for the latter compound. If the biosynthesis of eucosterol(1) is similar, hydroxylation at C (17) and ring closure at C(23) would precede elimination of a carbon atom at the terminus of the side chain. A reversed process by which C(23) is hydroxylated first, followed by the attack of this hydroxyl group at the 416 double bond cannot be excluded.…”

“…Chitt. was elucidated by chemical correlation of its methyl ester 17 with a degradation product of eucosterol (1).…”

Biochemical characterization of plant biotin-containing enzymes

“…Geranoic acid was prepared by oxidation of citral with Ag20 as described by Shamma and Rodrfguez (1968). Geranoyl-CoA was synthesized by the mixed anhydride method of Stadman (1957), with slight variations.…”