Aldehydes—Cont

Table 2.40 Asymmetric Aldol Reaction of Ketones and Aromatic Aldehydes —cont d...

Table 2.44 Knoevenagel Condensation of Malononitrile and Aldehydes—cont,d...

RibA-Catalyzed Aldol Addition of Acetone, Fiuoroacetone, and Acetaldehyde Donors to Various Aldehydes (cont)... 

Figure 2-1. Levels of Significant Exposure to Endrin/Endrin Aldehyde - Inhalation (cont.)... 

Ansari GAS, Gan JC, Barton BK. 1988. Synergistic inactivation of plasma alpha-proteinase inhibitor by aldehydes of cigarette smoke with styrene oxide and 1,2-dichloroethane. Arch Environ Cont Toxicol 17 533-536. 

A bacterial isolate APN has been shown to convert a-anunopropionitril enantioselectively to L-alanine (94% yield, 75% e e). However, ttie major disadvantage of tius approach, is the low stability of most aminonitriles in water (for example a-aminophenylacetonitrile in water of pH 7, degrades cont letely wifhin 48 hours). The aminonitriles are always in equilibrium with the aldehyde or ketone and ammonia/HCN. Polymerisation of hydrogen cyanide gives an equilibrium shift resulting in the loss of the aminonitrile. Therefore, a low yield in amino adds is to be expected, which makes this method less attractive for the industrial syntiiesis of optically active amino adds. 

What e.xplanation may be given for the failure of the aldehyde group in glucose to react with the reagent When dealing with water-insoluble cont-pound.s 2 cc of pure alcohol may be added. 

Addition of Pyruvate to Aldehydes Catalyzed by 2-Keto-3-deoxy-6-phospho-D-gluconate (GIcA), 2-Keto-3-deoxy-6-phospho-D-galactonate aldolases (GalA), and Macrophomate Synthase (MPS) (cont.)... 

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