Amine conjugating

The major competing reaction in acyl azide coupling is hydrolysis. The higher the pH, the faster the reactivity, both with regard to amine conjugation and hydrolysis. Crosslinkers or modification reagents containing this compound must be kept dry to preserve activity. Reactions are complete in 2-4 hours at room temperature. 

Vinyl substitutions on alkenes not having their double bonds conjugated with carbonyl groups often proceed more rapidly and give better product yields when the reactions are conducted in the presence of an unhindered secondary amine. Conjugated and nonconjugated dienes are usually only minor products in these cases. The major products normally are allylic amines obtained by nucleophilic attack of the secondary amine upon the ir-allylpalladium intermediates. Since allylic amines may be quatemized and subjected to the Hoffmann elimination, this is a two-step alternative to the direct vinyl substitution reaction.90... 

Palladium acetate triarylphosphine complexes catalyze the addition of vinylic groups from vinylic halides to olefinic compounds in the presence of amines. Conjugated dienes are major products from 0,/3-unsaturated acids, esters, or nitriles while unactivated olefinic compounds react best in the presence of secondary amines where allylic amines are major products. The reactions are usually regio- and stereospecific. The synthetic utility of the reaction is illustrated with a wide variety of examples. 

Periodate Oxidation/Reductive Amination Conjugation Protocols... 

Gipple KJ, Chan KT, Elvin AT, et al. Species differences in the urinary excretion of the novel primary amine conjugate tocainide carbamoyl O-beta-D-glucuronide. J Pharm Sci 1982 71 1011-1014. 

Del Duca, S., Dondini, L., Mea, M.D., De Rueda, P.M., and Serafini-Fracassini, D., Factors affecting transglutaminase activity catalyzing poly amine conjugation to endogenous substrates in the entire chloro-plast, Plant Physiol. Biochem., 38, 429-439, 2000. 

Occurrence of /3-Phenethyi.amine Conjugates and Related Compounds in Plants... 

A one-pot cascade reductive amination, conjugate addition and lactamisation of keto acrylate 112 afforded fused piperidinodiazepinone 113 in good yield <07T7187> while lactamisation was the final step in the synthesis of tetracyclic diazepinone natural products sclerotigenin and (-)-circumdatin-F <07TL3243>. 

The demonstration that modificationsmay induce nuclease stability sufficient to enhance activity in cells in tissue culture and in animals has proved to be much more complicated because of the presence of 5 -exonucleases and -endonucleases. In our laboratory, 3 -modifi-cations and internal point modifications have not provided sufficient nuclease stability to demonstrate pharmacological activity in cells (183). In fact, even a 5-nucleotide-long phos-phodiester gap in the middle of a phosphoro-thioate oligonucleotide resulted in sufficient loss of nuclease resistance to cause complete loss of pharmacological activity (164). In mice, neither a 5 -cholesterol nor 5 -C18 amine conjugate altered the metabolic rate of a phospho-rothioate oligodeoxynucleotide in liver, kid-... 

The a,(3-unsaturated ester (8), aldehyde (9), and nitro (10) compounds participate as electrophiles in a number of useful conjugate addition reactions. Copper-catalyzed addition of Grignard reagents provides access to aryl butanoic acid derivatives substituted with an oxetane (equation 1 in scheme 13.7). The ester, aldehyde, and nitro electrophiles also undergo mild Rh-catalyzed additions of aryl and vinyl boronic acids (equation 2 through equation 4 in scheme 13.7). Interestingly, the unsaturated aldehyde participates readily in an amine conjugate addition to afford oxetane substituted 3-amino-acetaldehyde derivatives. 

Amination. Conjugated dicarbonyl compounds are aminated with methoxyamine via an addition-elimination process. ... 

Figure 4.5-1. Chemical structures of activated PEGs for amine conjugation (a) PEG-dichlorotriazine (b) PEG-tresylate (c) PEG-aldehydes (d) PEG-succinimidyl succinate (e) PEG-imidazole carbonate (f) PEG-phenyl carbonate (g) PEG-succinimidyl carbonate (h) PEG-benzotriazole carbonate and (i) PEG-active ester.

A novel synthetic strategy and optical properties of highly fluorescent, triazine-amine conjugated oligomers 56 were described by Fujita and Murase. The oligomers can be expressed as (2 +l)-mer, where n represents the number of triazine rings in the oligomer (Scheme 7). 

Reduction with metal and ammonia or an amine conjugated systems... 

Finally, a double conjugate addition of MeNH2 to the dienone forms the bicyclic amine. Conjugate addition probably occurs first on the more electrophilic chloroenone, though it doesn t much matter. There is some stereoselectivity in that the remaining chlorine prefers the equatorial position on the new six-membered ring but this is thermodyanmic control as that position is easily enoUzed. 

Novel diene complexes of the type [Fe(T7-C5Me5)(CO)(r7 -diene)]" (37) have been synthesized and the kinetics of addition of amines to the diene ligand measured for the 1,3-cyclohexadiene complex/ A Br0nsted plot of log k vs. of amine conjugate acid has a slope of 0.3, which is much lower than that previously reported for amine addition to [Fe(CO)3(T7 -dienyl)]" cations. This was interpreted in terms of an essentially soft character for the complexed diene in (37). However, the low Br0nsted slope may arise from a saturation effect associated with the highly basic nature of the amines (morpholine, N-methylpiperazine, pyrrolidine, piperidine) employed in the more recent study. 

A disadvantage of the use of pyrene is that the extent of excimer formation depends on the bulk concentration of pyrene in the membranes. For this reason, several groups have synthesized covalently linked pyrenes or pyrene-amine conjugates. " Examples of such molecules are... 

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