Ficin as a catalyst in organic syntheses

Abstract

Examines the chemistry of ficin, particularly its catalytic behavior, and suggests experiments involving this natural substance.

Proteinase‐Catalyzed Synthesis of Peptide Bonds

“…Ficin has also been employed to resolve DL-amino acids through the formation of anilides (220). The enzyme preparations employed in these studies have since been recognized to represent a mixture of at least six components, two of which were crystallized (221), but their specificity has not yet been studied in a systematic manner.…”

Base-induced cyclization of 2-oximinophosphonium salts. Synthesis and spectroscopic properties of 1,2,5-oxazaphosph(V)ol-2-ines

“…Under these conditions, however, the oximation requires many hours at water-bath temperature, and in some cases, does not occur at all. An attempt at oximation of the phosphonium salt (8)11 by hydroxylamine hydrochloride failed even after 6 days at 80°, and attempts with free or partially free hydroxylamine resulted in the formation of the ylide (9). The phosphonium salts that we have obtained by these two methods are listed in Table I.…”

“…1,2,5-Oxazaphosph (V) oI-2-ines (4) are in general crystalline solids with melting points rather lower than the corresponding salts. When R and R'" are aromatic they are scarcely soluble in the common organic (8) For a recent review on this subject, see A. J. Kirby and S. G. Warren, "The Organic Chemistry of Phosphorus," Elsevier Publishing Co., 1967, p 117; see also I. J. Borowitz and H. Parnés, J. Org.…”

“…1-Benzoylbenzyltriphenylphosphonium Bromide (8).11-Desyl bromide30 (9.0 g, 32.7 mmol) dissolved in 100 ml of dry benzene was refluxed for 5 hr together with 8.6 g (32.7 mmol) of triphenylphosphine. After cooling, the whole mixture was shaken with water.…”