Vol.13, No.1 | 2015 | hypothesisjournal.com ABSTRACT Experimental conditions were devised, imitating prebiotic conditions in hydrothermal vents, to examine the possible prebiotic role of free purine bases in the direct synthesis of amino acids. Hypoxanthine, the biochemical precursor of adenine and guanine, was able to capture nitrite ions and be reductively transformed into adenine. Transfer o...

Predicting site selectivity in C-H bond oxidation reactions involving heteroatom transfer is challenged by the small energetic differences between disparate bond types and the subtle interplay of steric and electronic effects that influence reactivity. Herein, the factors governing selective Rh2(esp)2-catalyzed C-H amination of isoamylbenzene derivatives are investigated, where modification to ...

The literature reveals many references to transamination by bacteria. Two well substantiated works are those of Cutinelli (1945) and Lichstein and Cohen (1945). Goodlow, Mika, and Braun (1950) and Altenbern and Housewright (1951) have demonstrated synthesis of alanine by BruceUa abortus involving this method. Altenbern and Housewright also showed that their organism was capable of direct or red...

In our ongoing efforts in preparing tool compounds for investigating and controlling the biosynthesis of phenazines, we recognized the limitations of existing protocols for C–N bond formation of electron-deficient anilines when using reductive amination. After extensive optimization, we have established three robust and scalable protocols for the reductive amination of ketones with electron-def...

In this work, the neutral and basic impurities found in the precipitate of MDMA(*)HCl are presented. MDMA.HCl was prepared by the most popular synthesis methods used in clandestine manufacture, i.e. safrole bromination, Leuckart method and reductive amination with various reducing agents: Al/Hg, NaBH(4), NaBH(3)CN. 3,4-Methylenedioxyphenyl-2-propanone (MDP-2-P), the starting material in Leuckar...

Disaccharides tagged with p-aminobenzoic acid (ABA) were separated by capillary electrophoresis (CE) and analyzed on-line with negative ion electrospray ionization tandem mass spectrometry (ESI/MS/MS). The formation of glycosylamine instead of reductive amination was selected as the derivatization reaction. In negative ion ESI, the glycosylamine approach provides more information on linkage and...

A short synthesis of 1,4-dideoxy-1,4-imino-D-arabinitol (DAB) and a formal synthesis of australine are described. In both cases, D-fructose is employed as the starting material and converted into a protected methyl 6-deoxy-6-iodo-furanoside. Zinc-mediated fragmentation produces an unsaturated ketone which serves as a key building block for both syntheses. Ozonolysis, reductive amination with be...

Stereodefined enol derivatives of aldehydes are prepared from terminal alkynes. Specifically, terminal alkynes are known to undergo Cp2ZrCl2-catalyzed methylalumination. Here, we show that the resultant vinylalanes can be oxygenated with peroxyzinc species to generate trisubstituted enolates. Electrophilic trapping with carboxylic anydrides or silyl triflates yields trisubstituted enol esters o...

The Pd-catalyzed oxidative olefin amination of the zinc bromide complex intermediate, formed by the sequential reaction of nitriles with a Reformatsky reagent and 1-alkynes, affords pyrrole derivatives in good to excellent yields. This tandem protocol provides a simple, efficient, and atom- and pot-economical way to quickly build polysubstituted NH-pyrroles starting from readily available reage...

A bright blue fluorescent graphene oxide that originates from passivation of surface reactive sites by amide formation and ring-opening amination of epoxide has been prepared. The surface polarity and charges of the fluorescent graphene oxide can synchronously be tuned by varying the used alkylamines.