Hydrazine derivative synthesis by trifluoroacetyl hydrazide alkylation

2020 ◽  
Vol 98 (9) ◽  
pp. 485-494
Author(s):  
Pradeep S. Chauhan ◽  
Skye Brettell ◽  
Mulamreddy Ramakotaiah ◽  
Sitan Diarra ◽  
Anh Minh Thao Nguyen ◽  
...  

N′-Alkyl hydrazides were effectively synthesized by routes featuring installation, alkylation, and removal of a trifluoroacetyl group. A set of amino acid derived hydrazides were acylated using trifluoroacetic anhydride, and the resulting trifluoroacetyl hydrazides were alkylated with alcohols in Mitsunobu reactions and with alkyl halides under alkaline conditions. Removal of the trifluoroacetyl group was affected under reductive and hydrolytic conditions to provide the respective N′-alkyl hydrazides. This three-step process may be performed without isolation of intermediates to yield N′-alkyl hydrazide after a single chromatographic purification.

1994 ◽  
Vol 267 (6) ◽  
pp. E877-E885 ◽  
Author(s):  
I. Tauveron ◽  
D. Larbaud ◽  
C. Champredon ◽  
E. Debras ◽  
S. Tesseraud ◽  
...  

The experiment was carried out to clarify the roles of insulin and amino acids on protein synthesis in fed lactating goats (30 days postpartum). Protein synthesis in the liver and various skeletal muscles was assessed after an intravenous injection of a large dose of unlabeled valine containing a tracer dose of L-[2,3,4-3H]valine. The animals were divided into three groups. Group I was infused with insulin (1.7 mumol/min) for 2.5 h under glucose, potassium, and amino acid replacement. Group A was infused with an amino acid mixture to create stable hyperaminoacidemia for 2.5 h. Group C animals were controls. The fractional synthesis rates (FSR) were 31.5 +/- 2.2, 6.5 +/- 0.4, 4.3 +/- 0.8, 4.0 +/- 1.2, 3.9 +/- 1.2, and 3.6 +/- 0.4%/day (SD) in liver, masseter, diaphragm, anconeus, semitendinosus, and longissimus dorsi, respectively, for group C. Neither hyperinsulinemia in group I nor hyperaminoacidemia in group A had not affected by hyperinsulinemia but was stimulated by hyperaminoacidemia (+30%, P < 0.05). In contrast to previous experiments in which a labeled amino acid was constantly infused, this study revealed a stimulating effect of amino acids on protein synthesis in the liver but not in skeletal muscles. As previously observed in studies with the constant-infusion method, insulin had no effect on protein synthesis.


Author(s):  
Isha Sunil ◽  
Chejerla Sunitha ◽  
Harkirat Kaur

Background: Decreased amniotic fluid is related to adverse maternal and perinatal outcomes. The purpose of this study was to evaluate the role of amino acid infusion in patients of oligohydromnios and compare the perinatal outcome in the two groups.Methods: This study was conducted in the Department of Obstetrics and Gynaecology, ASCOMS Hospital, Jammu for a period of one year from October 2017 to September 2018. A total of 50 women with AFI <8 cm were enrolled in the study . They were divided into two groups of 25 each. Group A were given amino acid infusion and Group B were not given any intervention. These were compared for increase in AFI and perinatal outcome.Results: In the present study, the gain in AFI in Group A was 2.32 ± 0.67 and in group B was 1.32 ± 1.03 which was statistically significant. The perinatal outcome was better Group A compared to Group B with decreased incidence of meconium stained liquor, low birth weight, low APGAR scores and NICU admissions and increase in vaginal deliveries as compared to caesarean sections.Conclusions: The present study suggests that parentral transfusion of amino acid in cases of oligohydromnios significantly increases the AFI of the patient and decreases the incidence of caesarean sections, meconium stained liquor, low APGAR scores and NICU admissions.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
N Adel ◽  
M Kadah ◽  
S Abdulghafar ◽  
M Elmahdy ◽  
D Ghareeb ◽  
...  

Abstract Study question How to determine human embryo viability noninvasively before embryo transfer? Summary answer We propose that the combination of the amino acid profile of an individual embryo with its morphokinetics will provide noninvasive tool to determine its viability. What is known already It was already known that human embryos at early cleavage require non-essential amino acids, while at the 8-cell to blastocyst stages, a mixture of non-essential and essential amino acids. Amino acids have important roles during embryo development. Acting as biosynthetic precursors,buffers of intracellular pH in the embryo, antioxidants, energy sources and regulators of metabolic function and signaling pathways. Many studies have used time-lapse to analyze human embryonic development including the process of fertilization and assessment of early events and introducednoninvasive prognostic markers which predict embryo development and correlate it to IVF treatment outcomes. Study design, size, duration This study was a prospective cohort study approved by the Clinical Trial Ethical Committee of Faculty of Medicine, Alexandria University according to ethical standards of scientific research (Serial number: 0303721).Thirty females aged 30.13 ± 4.83 years undergoing ICSI cycle in the Madina Fertility Center, during the period of March 2018 to November 2019.202 MII oocytes were incubated individually in embryoscope. Participants/materials, setting, methods Embryos (n = 161) were divided on Day 5 into two groups –developed embryos “Group D” (embryos that developed to blastocyst) and arrested embryos “Group A” (embryos remain at cleavage stage and fail to develop to blastocys).Developed embryos (Group D) included 99 embryos, and Arrested embryos (Group A) included 62 embryos. For each group, morphokinetic developmental points using embryoscope and the different amino acids concentrations in spent culture medium were analyzed using LC- mass spectro etry. Main results and the role of chance On one hand, the first appearance of pronuclei (TPNa), t2, t4 and CC2 in group D occurred significantly earlier than those of Group A.Analysis of 19 essential and non-essential amino acids in spent culture medium of each embryo in the two studied groups D and A showed a significantly higher concentration of two essential amino acids L-Valine (145.73 ± 150.96) and L-Phenylalanine (61.59 ± 55.78) in Group D than their concentration in Group A ( 104.58 ± 33.58, 44.24 ± 14.61, respectively , p ≤ 0.05).and significantly lower concentration of three non-essential amino acids L-Tyrosine (62.56 ± 41.03) , L-Cysteine (19.48 ± 11.90), and L-Alanine (136.0 ± 389.83) observed in Group D when compared to Group A (69.57 ± 20.78, 22.37 ± 8.59,145.33 ± 165.22, respectively, Limitations, reasons for caution It is important to note, that results were developed on a data set from one clinic with different stimulation protocols, a multicenter data and a correlation with the stimulation protocol used should be involved in future studies, in addition a larger sample size to avoid high standard deviation is recommended Wider implications of the findings: We can conclude that amino acid turnover is independent of the traditional morphological assessment of embryos and it may reflect its viability. The prospective combined use of amino acids profile of individual embryo and its morphokinetic parameters may contribute to introduce a new noninvasivs tool that may improve implantation rate Trial registration number 0303721


2020 ◽  
Vol 56 (21) ◽  
pp. 3222-3224
Author(s):  
Stuart Johnson ◽  
Ervin Kovács ◽  
Michael F. Greaney

A variety of quaternary aryl amino acid derivatives can be synthesised using tandem SN2/Smiles rearrangement chemistry involving aryl sulfonamides and α-chloro carbonyl compounds.


2020 ◽  
Vol 88 (11) ◽  
Author(s):  
Paul E. Bernard ◽  
Amey Duarte ◽  
Mikhail Bogdanov ◽  
James M. Musser ◽  
Randall J. Olsen

ABSTRACT Group A Streptococcus (GAS) is a human-specific pathogen and major cause of disease worldwide. The molecular pathogenesis of GAS, like many pathogens, is dependent on the coordinated expression of genes encoding different virulence factors. The control of virulence regulator/sensor (CovRS) two-component system is a major virulence regulator of GAS that has been extensively studied. More recent investigations have also involved regulator of Cov (RocA), a regulatory accessory protein to CovRS. RocA interacts, in some manner, with CovRS; however, the precise molecular mechanism is unknown. Here, we demonstrate that RocA is a membrane protein containing seven transmembrane helices with an extracytoplasmically located N terminus and cytoplasmically located C terminus. For the first time, we demonstrate that RocA directly interacts with itself (RocA) and CovS, but not CovR, in intact cells. Single amino acid replacements along the entire length of RocA disrupt RocA-RocA and RocA-CovS interactions to significantly alter the GAS virulence phenotype as defined by secreted virulence factor activity in vitro and tissue destruction and mortality in vivo. In summary, we show that single amino acid replacements in a regulatory accessory protein can affect protein-protein interactions to significantly alter the virulence of a major human pathogen.


2019 ◽  
Vol 4 (1) ◽  
Author(s):  
Stephanie P Gilley ◽  
Nicholas E Weaver ◽  
Evan L Sticca ◽  
Purevsuren Jambal ◽  
Alexandra Palacios ◽  
...  

ABSTRACT Background Maternal dietary restriction and supplementation of one-carbon (1C) metabolites can impact offspring growth and DNA methylation. However, longitudinal research of 1C metabolite and amino acid (AA) concentrations over the reproductive cycle of human pregnancy is limited. Objective To investigate longitudinal 1C metabolite and AA concentrations prior to and during pregnancy and the effects of a small-quantity lipid-based nutrition supplement (LNS) containing &gt;20 micronutrients and prepregnancy BMI (ppBMI). Methods This study was an ancillary study of the Women First Trial (NCT01883193, clinicaltrials.gov) focused on a subset of Guatemalan women (n = 134), 49% of whom entered pregnancy with a BMI ≥25 kg/m2. Ninety-five women received LNS during pregnancy (+LNS group), while the remainder did not (−LNS group). A subset of women from the Pakistan study site (n = 179) were used as a replication cohort, 124 of whom received LNS. Maternal blood was longitudinally collected on dried blood spot (DBS) cards at preconception, and at 12 and 34 wk gestation. A targeted metabolomics assay was performed on DBS samples at each time point using LC-MS/MS. Longitudinal analyses were performed using linear mixed modeling to investigate the influence of time, LNS, and ppBMI. Results Concentrations of 23 of 27 metabolites, including betaine, choline, and serine, changed from preconception across gestation after application of a Bonferroni multiple testing correction (P &lt; 0.00185). Sixteen of those metabolites showed similar changes in the replication cohort. Asymmetric and symmetric dimethylarginine were decreased by LNS in the participants from Guatemala. Only tyrosine was statistically associated with ppBMI at both study sites. Conclusions Time influenced most 1C metabolite and AA concentrations with a high degree of similarity between the 2 diverse study populations. These patterns were not significantly altered by LNS consumption or ppBMI. Future investigations will focus on 1C metabolite changes associated with infant outcomes, including DNA methylation. This trial was registered at clinicaltrials.gov as NCT01883193.


2008 ◽  
Vol 89 (7) ◽  
pp. 1690-1698 ◽  
Author(s):  
Andrej Steyer ◽  
Mateja Poljšak-Prijatelj ◽  
Darja Barlič-Maganja ◽  
Jožica Marin

A surveillance of human, porcine and bovine rotaviruses was carried out in Slovenia in 2004 and 2005. Stool samples were collected from a total of 406 pigs (373 from asymptomatic animals), 132 cattle (126 from asymptomatic animals) and 241 humans (all with diarrhoea), tested for group A rotaviruses using RT-PCR and analysed by sequencing. The aims of the study were to determine the incidence of asymptomatic rotavirus infection in animals, to look for evidence of zoonotic transmission and to detect reassortment among rotaviruses. The rates of asymptomatic shedding of rotaviruses in pigs and cattle were 18.0 % (67/373) and 4.0 % (5/126), respectively. Evidence for zoonotic transmission was detected in one human rotavirus strain, SI-MB6, with the G3P[6] genotype combination, as the nucleotide and predicted amino acid sequences of the VP6, VP7, VP8* and NSP4 genes of strain SI-MB6 and of porcine strains showed high nucleotide and amino acid sequence identity. Two porcine rotavirus strains carried VP7 of probable human origin, suggesting an interspecies reassortment event in the past.


2013 ◽  
Vol 9 ◽  
pp. 2378-2386 ◽  
Author(s):  
Diego Carnaroglio ◽  
Katia Martina ◽  
Giovanni Palmisano ◽  
Andrea Penoni ◽  
Claudia Domini ◽  
...  

A fast and efficient protocol for the synthesis of N,N'-disubstituted urea derivatives from alkyl halides and primary or secondary amines has been developed. The synthetic pathway combines nucleophilic substitutions and a Staudinger–aza-Wittig reaction in the presence of polymer-bound diphenylphosphine under 14 bar of CO2 pressure and has been performed in a one-pot two-step process. The protocol has been optimized under microwave irradiation and the scale-up experiment has been conducted under conventional conditions in a Parr reactor. The final compounds were isolated after simple filtration in almost quantitative overall yields which makes this procedure facile and rapid to execute.


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