ABSTRACT
We have previously reported the first formal hydroamination of enamines for the synthesis of chiral 1,2-diamines. Here, we describe: (i) the discovery, optimization, and substrate expansion of this reaction; (ii) a novel and straightforward protocol for the "click-type" synthesis of enamines in quantitative yield utilizing sodium sulfate in a dual role as an ancillary and dehydrating agent without the need for workup or purification; (iii) the application of this methodology to the first enantioselective synthesis of orthogonally protected 1,1'-(1-(4-fluorophenyl)ethane-1,2-diyl) piperazines, a scaffold for rapid lead optimization in drug discovery; (iv) a computational investigation into the mechanism and rationalization of the enantioselectivities of the reaction.
ABSTRACT
BACKGROUND: With the potential development of human pathogenic bacteria resistant to antibiotics, the use of antibiotics as growth promoter in poultry production was banned in different countries, and it has forced the poultry industry to consider 'Biologically safer' alternatives to antibiotics, among which the probiotics and microalgae can be mentioned. OBJECTIVE: Present study aimed to compare Spirulina platensis microalgae in combination with a native probiotic as an alternative to antibiotics. METHODS: 336 male broiler chicks were allotted into 7 treatments and 4 repetitions in a completely randomised design to evaluate chick's performance and immune response to different treatment based on indexes as feed intake, weight gain, feed conversion ratio, humoral immunity, carcass characteristics, thigh and breast pH, intestinal morphology and microbial population. European production efficiency coefficient was also reported. RESULTS: No significant difference was appeared in the pH of thigh and breast meat (p > 0.05). Supplementation of diets with SP0.3 revealed better villi height, villi length to crypt depth ratio and villi surface. With significant difference (p < 0.05), the highest and lowest colonies of Lactobacillus and E. coli were recorded for PR0.5 SP0.3 treatments. CONCLUSIONS: Supplementation of broilers diets either with probiotic prepared from the microorganism isolated of native birds (1 g/kg) or S. platensis (0.2 g/kg) alone and their combination (0.3 g/kg of S. platensis in combination with 0.5 g/kg of native probiotic) are promising and can be a good alternative to antibiotics, lead to progress of broiler's performance.
Subject(s)
Gastrointestinal Microbiome , Microalgae , Probiotics , Animals , Male , Chickens/physiology , Escherichia coli , Immunity , Meat/analysis , Powders , Probiotics/pharmacologyABSTRACT
The synthesis of primary and secondary pinacol boronic esters via lithiation-borylation of carbamates and benzoates with pinacolborane is described. This new protocol enables the highly selective synthesis of enantioenriched and geometrically defined boronic esters that cannot otherwise be accessed by alternative methodologies.