Microwave-prompted Rapid and Efficient Synthesis of Diacyl Thiosemicarbazides and Semicarbazides in Solvent and Catalyst Free Condition

Eighteen 1-aroyl-4-（2-iodobenzoyl）thiosemicarbazides and corresponding semicarbazides were synthesized in excellent yield under microwave irradiation in solvent and catalyst free condition.

Sources, Toxicity and Detection Techniques of Semicarbazide: A Review

Semicarbazide has become an important pollutant in the environment,but there was no comprehensive literature on its advances.In this review,the source,biotoxicity and detection methods are summarized.Among the sources is the material of chemical reaction,a metabolite of nitrofurazone,food processing(production by azobisformamide and hypochlorite treatment),endogenous substances,etc.Semicarbazide is demonstrated to be accumulative and reproductive toxicity,mutagenicity and genotoxicity,endocrine disruptors,and neurotoxicity.There are still many controversies on the effect of genotoxicity and no clear result on the carcinogenic mechanism.HPLC-MS/MS is the mainstream of the detection methods.Other methods,including HPLC,immunoassay method,biosensor method,electrochemical detection,capillary electrophoresis technique,and spectral techniques mainly,have become less and less in recent years.On all these counts,to reduce the content of semicarbazide in the environment,the key is to control the use of nitrofurazone as the banned drug effectively.Meanwhile the toxicity data should be supplemented to reveal its toxic mechanism.

Novel High-nitrogen Energetic Compound Based on Semicarbazide-substituted Tetrazine

A novel energetic compound 3-（3,5-dimethylpyrazol-1-yl）-6-semicarbazide-1,2,4,5-tetrazine（DSTZ） was prepared and characterized by elemental analysis and Fourier transform infrared（FTIR） spectroscopy.The crystal structure was determined by X-ray single crystal diffraction technology.The crystal belongs to the monoclinic system with a P2 1 /c space group,a=0.9942（7） nm,b=0.5067（3） nm,c=1.1830（8） nm,β=109.616°,Z=2 and D c =1.475 g/cm 3.With extensive hydrogen bonds,the molecules were linked together to form a three-dimensional herringbone-like pattern.Thermal analysis of the compound was carried out via differential scanning calorimetry（DSC） and thermogravimetric-derivative thermogravimetry（TG-DTG）.Under a nitrogen atmosphere at a heating rate of 10 K/min,DSTZ decomposed directly in a range of 493―513 K.Only one intense exothermic process was observed and the decomposition products were all gaseous products.Conventional sensitivity properties were determined,showing that the title complex was insensitive to friction,impact and flame.

The New Synthesis of Azo Urea from Substituted Semicarbazide

Using N-bromosuccinimide and pyridine as the oxidation system to dehydrogenate aryl substituted semicarbazide to form azo compounds is described for the first time in this paper. Nine azo compounds have been prepared in excellent yield under mild condition. This method only. needs simple instrument and short reaction time.

Insight into solute-solute and solute-solvent interactions of semicarbazide hydrochloride in water and D-glucose/D-sucrose+water solutions at temperatures(293.15 to 318.15)K

The solute-solute and solute-solvent interactions of drug semicarbazide hydrochloride with carbohydrates(Dglucose/D-sucrose)are investigated by using volumetric,viscometric and acoustic properties.The measurements of the densitiesρ,ultrasonic speeds u,and viscositiesη.of semicarbazide hydrochloride in 5% and 10%D-glucose/D-sucrose+water(w/w)solutions were carried out at temperatures(293.15-318.15)K and at pressure,p=101 kPa.The apparent molar volumes,Vϕ,limiting apparent molar volumes,V°ϕ,apparent molar compressibilities,Ks,ϕ,limiting apparent molar compressibilities,K°s;ϕ,partial molar expansibilities,E°ϕ,transfer volumes,V°ϕ;tr and transfer compressibilities,K°s;ϕ;tr have been calculated from the experimental data.The viscosity data were examined by using the Jones-Dole equation and the viscosity A and B coefficients were evaluated.The results are discussed in terms of solute-solute and solute-solvent interactions in these solutions.The structure making/breaking ability of semicarbazide hydrochloride is examined using the sign of temperature derivative of Bcoefficient,dB/dT.

Novel assay for identification of semicarbazide-sensitive amine oxidase by a priority-based strategy in mass spectrometry

A novel assay for the identification of semicarbazide sensitive amine oxidase in human umbilical artery tissue by a priority based strategy in the mass spectrometry was developed. The pro tein extract was separated by SDS PAGE, and then an entire band at 96 KDa was excised and digested by trypsin. The digested peptides were separated by capillary ClS analytical column and detected by ESI MS MS. In the direct data dependent method （also called traditional method）, the semicarbaz ide sensitive amine oxidase （SSAO） cannot be identified by LC-ESI-MS-MS. Compared with the tra ditional method, our assay by a priority based strategy in the mass spectrometry can successfully identify the target protein SSAO in the complex biological sample. As 60 μg, 120μg, 240 μg of total protein extract were loaded on the SDS PAGE, the Mascot result showed that SSAO score was 46, 86 and 137, the sequence coverage was 2 % , 5 % and 10 % , and the peptide count was 2, 6 and 10, re spectively. The MS/MS spectra of two unique peptides of SSAO were confirmed by manual identifica tion. The band at 96 KDa included SSAO was validated by the Western blot. The assay significantly improved the score and coverage of target protein and enhanced the identification of reliability and the confidence.

Suppression of deep‑level traps via semicarbazide hydrochloride additives for high‑performance tin‑based perovskite solar cells

Tin perovskites with exemplary optoelectronic properties ofer potential application in lead-free perovskite solar cells.However,Sn vacancies and undercoordinated Sn ions on the tin perovskite surfaces can create deep-level traps,leading to nonradiative recombination and absorption of nucleophilic O_(2)molecules,impeding further device efciency and stability.Here,in this study,a new additive of semicarbazide hydrochloride(SEM-HCl)with a N–C=O functional group was introduced into the perovskite precursor to fabricate high-quality flms with a low concentration of deep-level trap densities.This,in turn,serves to prevent undesirable interaction between photogenerated carriers and adsorbed oxygen molecules in the device’s operational environment,ultimately reducing the proliferation of superoxide entities.As the result,the SEM-HCl-derived devices show a peak efciency of 10.9%with improved device stability.These unencapsulated devices maintain almost 100%of their initial efciencies after working for 100 h under continuous AM1.5 illumination conditions.

Flash Pyrolysis Study of M2TNR （M： Carbohydrazide or Semicarbazide） by T-jump/FTIR Spectroscopy

Flash pyrolysis of （CHZ）2TNR and （SCZ）2TNR was conducted by T-jump/FTIR spectroscopy under 0.1 MPa Ar atmosphere. The results show that eleven IR-active gas products obtained during flash pyrolysis process of the two title compounds are NO, CO, HCN, NH3, NO2, N2O, HNCO, HNO2, CO2, H2O and HCHO, of which NO and CO are the main gas products. The molar fraction of the individual product in the pyrolysis gas mixture was described as a function of time. At least some of the NO2, N2O and H2O can result from the oxidization reaction of NH3 during flash pyrolysis of （CHZ）2TNR. It can be concluded that the two compounds are not worthy of further in-depth consideration of the adoption in detonators as eco-friendly primary explosive, and should not be used as gas generation composition of automobile crash airbag system taking into account the toxicity.

Preparation and Molecular Structure of (SCZ)(TNPG)·2H_2O

The （SCZ）（TNPG）.2H2O prepared by mixing semicarbazide （SCZ） and trinitrophloroglucinol （TNPG） was characterized by elemental analysis and IR measurement, and its crystal structure was determined by X-ray single-crystal diffraction analysis. The crystal belongs to triclinic,space group P1, （NH2CONHNH3）^＋（C6H2N3O9）^-·2H2O, Mr = 372.23, a = 0.68853（14）, b =0.93966（19）, c = 1.1925（2） nm, α = 67.48（3）, β = 77.56（3）, γ = 78.93（3）°, V = 0.6908（2） nm^3, Z = 2,Dc = 1.789 g/cm^3, Mr = 373.23, F（000） = 384, S = 0.999 and μ（MoKa） = 0.172 mm^-1. The final R and wR are 0.0394 and 0.1057 for 1724 observed reflections with I 〉 2σ（I）. It is concluded that （SCZ）（TNPG） 2H2O is an ionic compound composed of a cation SCZ^＋, an anion TNPG- and two water molecules. The TNPG anion and SCZ^＋ cation are bonded together by electrostatic attraction and hydrogen bonds, and the compound structure is stable. The thermal decomposition of （SCZ）（TNPG） 2H2O was studied by using TG-DTG and DSC techniques with a heating rate of 10 ℃/min, showing the compound contains one endothermic process of dehydrating stage and two intensive exothermic decomposition stages. The enthalpy of exothermic decomposition reaction is 452.31 kJ/mol.

An Efficient Solid-State Synthesis of N-Aryl-2-phenyldiazenecarboxamides

A new and ancient solid-state reaction using K3Fe(CN)(6)/KOII to oxidize diaryl semicarbazides for preparing azo compounds has been reported. Nine N-aryl-2-phenyl-diazenecarboxamides have been synthesized in excellent yields with simple instrument.

A Simple and Rapid Method for Synthesis of N,2-Diaryl Diazcnecarboxamides

Using Fe2(SO4)3/H2SO4 as oxidant, nine N,2-diaryl diazcnecarboxamides weresynthesized from diaryl substituted semicarbazides in excellent yield under mild conditions for thefirst time. This method is simple, convenient and rapid.

Synthesis and Crystal Structure ofp-tert-Butylcalix[4]arene 1,3-Distal and Monosubstituted Semicarbazones and Thiosemicarbazones

A series of p-tert-butylcalix[4]arene 1,3-distal and monosubstituted semicarbazones and thiosemicarbazones was preparedd by acid catalyzed condensation reaction of active calixarene aldehydes with semi- carbazide and thiocarbazide in methanol. One representative single crystal was determined by X-ray dirraction method, which shows that calixarene exists in cone configuration and intramolecular hydrogen-bands exist in the crystal.

Green and Efficient Synthesis of 3-Pyrazolyl Indoles in Water

A green and efficient synthesis of 3-pyrazolyl indoles was developed by the eye 1 ocondensation reactionof β-ethylthio-β-indolyl-α,β-unsaturated ketones with semi carbazide hydrochloride as hydrazine equivalent in thepresence of 3 equiv. of PEG400(la/PEG mole ratio of 1:3) in reflux water. This procedure did not require toxichydrazine and product purification, eliminating the use of toxic liquid chemicals.