Solids containing varying amounts of formaldehyde, probably as paraformaldehyde (polymers of formula HO(CH2O)xH where x averages about 30). A hazard to the environment. Immediate steps should be taken to limit spread to the environment.
颜色/状态：
Nearly colorless gas [Note: Often used in an aqueous solution]. /Pure formaldehyde/
气味：
Pungent, suffocating odor
蒸汽密度：
1.067 (Air = 1)
蒸汽压力：
3,890 mm Hg at 25 °C /100% formaldehyde/
亨利常数：
Henry's Law constant = 3.37X10-7 atm-cu m/mol at 25 °C
大气OH速率常数：
9.37e-12 cm3/molecule*sec
稳定性/保质期：
On standing, especially in the cold, may become cloudy, and on exposure to very low temperature ppt of trioxymethylene formed; in air it slowly oxidizes to formic acid /40% solution/.
自燃温度：
795 °F (424 °C)
分解：
Uncatalyzed decomposition is very slow below 300 °C; extrapolation of kinetic data to 400 °C indicates that the rate of decomposition is about 0.44%/min at 101 kPa (1 atm). The main products are carbon monoxide and hydrogen. Metals such as platinium, copper, chromia, and alumina also catalyze the formation of methanol, methylformate, formic acid, carbon dioxide, and methane.
粘度：
0.1421 cP at 25 °C
腐蚀性：
Aqueous formaldehyde is corrosive to carbon steel, but formaldehyde in gas phase is not.
燃烧热：
570.7 kJ/mol (gas)
汽化热：
23.3 kJ/mol at 19 °C
表面张力：
27.3797 dyn/cm at 25 °C
电离电位：
10.88 eV
聚合：
Anhydrous, monomeric formaldehyde ... /a dry gas/ is relatively stable at 80-100 °C but slowly polymerizes at lower temp. Traces of polar impurities such as acids, alkalies, and water qreatly accelerate the polymerization. When liquid formaldehyde is warmed to room temp in a sealed ampule, it polymerizes rapidly with the evolution of heat (63 kJ/mol or 15.05 kcal/mol).
气味阈值：
Odor Threshold Low: 0.02 [ppm]; Odor Threshold High: 1.9 [ppm]; Odor threshold from CHEMINFO; In HSDB: odor threshold = 0.5-1 ppm; Odor threshold estimated at less than 0.5 ppm
折光率：
Index of refraction: 1.3746 at 20 °C/D /Formaldehyde soln/
When female rats were administered (14)C-formaldehyde ip at dose level of 70 mg/kg, 82% of dose was expired as (14)carbon dioxide and 13-14% was excreted via kidneys in form of methionine, serine, and formaldehyde-cysteine adduct.
Rats injected ip with 0.26 mg/kg (14)C-labeled formaldehyde ... excreted approx 22% of this dose in the urine over 5 days. Formic acid and a thiazolidine-4-carboxylic acid derivative were identified in urine as formaldehyde metabolites.
Several of the urinary excretion products of formaldehyde in rats have been identified after intraperitoneal administration of (14)C-formaldehyde. After injecting Wistar rats with 0.26 mg/kg body weight, ... formate and a sulfur-containing metabolite (thought to be a derivative of thiazolidine-4-carboxylic acid) and products presumed to result from one-carbon metabolism /were detected/. Thiazolidine-4-carboxylate, which is formed via the nonenzymatic condensation of formaldehyde with cysteine, was not detected in urine.
Formaldehyde absorbed into the bloodstream is metabolized to formic acid, which is excreted in the urine as the sodium salt or oxidized further to carbon dioxide and water. This detoxification process can deal efficiently with low concentrations of formaldehyde, but high concentrations cause acidosis and tissue damage.
Formaldehyde may be absorbed following inhalation, oral, or dermal exposure. It is an essential metabolic intermediate in all cells and is produced during the normal metabolism of serine, glycine, methionine, and choline and also by the demethylation of N-, S-, and O-methyl compounds. Exogenous formaldehyde is metabolized to formate by the enzyme formaldehyde dehydrogenase at the initial site of contact. After oxidation of formaldehyde to formate, the carbon atom is further oxidized to carbon dioxide or incorporated into purines, thymidine, and amino acids via tetrahydrofolatedependent one-carbon biosynthetic pathways. Formaldehyde is not stored in the body and is excreted in the urine (primarily as formic acid), incorporated into other cellular molecules, or exhaled as carbon dioxide. (L962)
IDENTIFICATION AND USE: Formaldehyde is a clear, water-white, very slightly acid, gas or liquid. It is registered for pesticide use in the U.S. but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses. Formaldehyde is used primarily as a fumigant in agricultural premises such as poultry and swine farms and processing plants as well as in citrus packing and mushroom houses. It is used as a hard surface disinfectant in commercial premises, industrial premises and veterinary clinics. Formaldehyde is also registered as a materials preservative for consumer products such as laundry detergents, general purpose cleaners and wall paper adhesives. There are no inert ingredient uses for this chemical. It is also used as an antimicrobial in biologics, topicals, hepatitis B vaccine, sterilizer for kidney dialysis membranes. Additional uses of formaldehyde in medicine include disinfecting hospital wards, preserving specimens, and as a disinfectant against athlete's foot. HUMAN EXPOSURE AND TOXICITY: Acute effects of airborne formaldehyde exposure: Odor detection, 0.05-1.0 ppm; Eye irritation, 0.01-2 ppm; Upper respiratory tract irritation (e.g., irritation of the nose or throat), 0.10-11 ppm; Lower airway irritation (e.g., cough, chest tightness, and wheezing), 5-30 ppm; Pulmonary edema, inflammation, pneumonia, 50-100 ppm; Death >100 ppm. Formaldehyde can provoke skin reactions in sensitized subjects, not only by contact but also by inhalation. According to IARC, there is sufficient evidence in humans for the carcinogenicity of formaldehyde. Formaldehyde causes cancer of the nasopharynx and leukemia. Also, a positive association has been observed between exposure to formaldehyde and sinonasal cancer. An investigation of reproductive function in female workers exposed to formaldehyde in the garment industry revealed increased incidence of menstrual disorders, inflammatory disease of the reproductive tract, sterility, anemia, and low birth weights among offspring. The published studies suggest that inhalation of formaldehyde leads to increased micronuclei frequencies in nasal and/or buccal mucosa cells. ANIMAL STUDIES: Acute effects in rats to low (<1 ppm) or moderate (10-50 ppm) of vapor resulted in increased airway resistance, decreased sensitivity of nasopalatine nerve, irritation of eyes and of respiratory system, and changes in hypothalamus. Exposure to high doses (above 100 ppm) caused salivation, acute dyspnea, vomiting, cramps and death. Hair depigmentation was observed in black mice at site of sc injection of 100 ug formaldehyde. Mice treated with formaldehyde on skin developed severe liver damage. Groups of 25 mated female rats were exposed by inhalation to formaldehyde (0, 2, 5 or 10 ppm (2.5, 6.2 or 12.3 mg/cu m) for 6 hr per day on days 6-15 of gestation. At 10 ppm, there was a significant decrease in maternal food consumption and weight gain. None of the parameters of pregnancy, including numbers of corpora lutea, implantation sites, live fetuses, dead fetuses and resorptions or fetal weights, were affected by treatment. An increased incidence of reduced ossification was observed at 5 and 10 ppm in the absence of maternal toxicity (10 ppm). Formaldehyde caused nasal squamous cell carcinomas in the rat following 2 year inhalation exposure. The incidence of this tumor in a historical data base of 16,794 rats was nil, indicating that it is a rare spontaneous tumor. Male and female rats of different ages at the start of the experiments (12 day embryos, and 7 and 25 weeks old) were administered formaldehyde in drinking water at different doses (2,500 or 1,500, 1,000, 500, 100, 50, 10, 0 ppm). An increased incidence of leukemias and of gastro-intestinal tumors was observed in formaldehyde treated rats. Gastro-intestinal tumors are exceptionally rare in the rats of the colony used. Formaldehyde induces gene mutation in bacteria, fungi, yeast, and Drosophila larvae as well as in cultured rodent and human cells. In part, these mutations appear to be the consequence of DNA damage. A second mechanism by which formaldehyde may damage the genome is inhibition of DNA repair. ECOTOXICITY STUDIES: It was concluded from the study that formalin feeding to female quails at 2.5 mL/kg feed is without harmful effects, however, higher doses are not without health risks.
It is likely that formaldehyde toxicity occurs when intracellular levels saturate formaldehyde dehydrogenase activity, allowing the unmetabolized intact molecule to exert its effects. Formaldehyde is known to form cross links between protein and DNA and undergo metabolic incorporation into macromolecules (DNA, RNA, and proteins). (L962)
There is sufficient evidence in humans for the carcinogenicity of formaldehyde. Formaldehyde causes cancer of the nasopharynx and leukaemia. Also, a positive association has been observed between exposure to formaldehyde and sinonasal cancer. There is sufficient evidence in experimental animals for the carcinogenicity of formaldehyde. The Working Group was not in full agreement on the evaluation of formaldehyde causing leukaemias in humans, with a small majority viewing the evidence as sufficient of carcinogenicity and the minority viewing the evidence as limited. Particularly relevant to the discussions regarding sufficient evidence was a recent study accepted for publication which, for the first time, reported aneuploidy in blood of exposed workers characteristic of myeloid leukaemia and myelodysplastic syndromes, with supporting information suggesting a decrease in the major circulating blood-cell types and in circulating haematological precursor cells. The authors and Working Group felt that this study needed to be replicated. Formaldehyde is carcinogenic to humans (Group 1).
来源:Hazardous Substances Data Bank (HSDB)
毒理性
致癌性证据
癌症分类：B1组，可能的人类致癌物
Cancer Classification: Group B1 Probable Human Carcinogen
CLASSIFICATION: B1; probable human carcinogen. BASIS FOR CLASSIFICATION: Based on limited evidence in humans, and sufficient evidence in animals. Human data include nine studies that show statistically significant associations between site-specific respiratory neoplasms and exposure to formaldehyde or formaldehyde-containing products. An increased incidence of nasal squamous cell carcinomas was observed in long-term inhalation studies in rats and in mice. The classification is supported by in vitro genotoxicity data and formaldehyde's structural relationships to other carcinogenic aldehydes such as acetaldehyde. HUMAN CARCINOGENICITY DATA: Limited. ANIMAL CARCINOGENICITY DATA: Sufficient.
Formaldehyde is absorbed readily from the respiratory and oral tracts and, to a much lesser degree, from the skin. It is the simplest aldehyde and reacts readily with macromolecules, such as proteins and nucleic acids. Inhalational exposure has been reported to result in almost complete absorption. Dermal absorption due to contact with formaldehyde-containing materials (e.g., textiles, permanent-press clothing, cosmetics, or other materials) is of low order of magnitude. ... Formaldehyde normally is converted and excreted as carbon dioxide in the air, as formic acid in the urine, or as one of many breakdown products from one-carbon pool metabolism. As a result of rapid absorption by both the oral and inhalational routes and its rapid metabolism, little or no formaldehyde is excreted unmetabolized. In rats exposed to (14)C-formaldehyde by inhalation, 40% of the radiolabel was excreted in the air and 20% in the urine and feces, whereas 40% remained in the carcass.
In rats and mice administered (14)C-formaldehyde intragastrically, 40% of dose... /was/ expired as carbon dioxide, 10% /was/ excreted in urine and 1% in feces after 12 hr; carcasses contained 20% after 24 hr and 10% after 4 days. When female rats were administered (14)C-formaldehyde ip at dose level of 70 mg/kg, 82% of dose was expired as (14)C dioxide and 13-14% was excreted via kidneys... .
Formaldehyde is absorbed rapidly and almost completely from the rodent intestinal tract. In rats, about 40% of an oral dose of (14)C-formaldehyde (7 mg/kg) was eliminated as (14)C-carbon dioxide within 12 hours, while 10% was excreted in the urine and 1% in the feces. A substantial portion of the radioactivity remained in the carcass as products of metabolic incorporation.
Four men and two women were exposed to a 1.9 ppm air concentration of formaldehyde in a large walk-in chamber for 40 minutes. Shortly before and shortly after the exposure, venous blood samples were taken from each person (each person served as his/her own control) and the blood was analyzed for formaldehyde content. Mean venous blood formaldehyde concentrations in humans prior to exposure showed a blood concentration of 2.61 + or - 0.41 ug/g of blood. Individual variability was markedly present. Immediately after a 40-minute exposure, mean blood concentration of formaldehyde was 2.77 + or - 0.28 ug/g of blood. There was no significant difference between pre- and postexposure blood concentrations of formaldehyde at the formaldehyde air concentrations tested in this study. This result suggests that formaldehyde was absorbed only into the tissues of the respiratory tract. The absence of increased formaldehyde concentrations in the blood is likely due to its rapid metabolism in these tissues and/or fast reaction with cellular macromolecules.
Stereoselective Synthesis of Medium-Sized Cyclic Ethers by Sequential Ring-Closing Metathesis and Tsuji–Trost Allylation
作者：James Skardon-Duncan、Michael Sparenberg、Alexandre Bayle、Sam Alexander、J. Stephen Clark
DOI：10.1021/acs.orglett.8b01082
日期：2018.5.4
Fully functionalized medium-sized cyclic ethers, of the type found in fused polyether natural products, have been prepared by sequential ring-closing diene metathesis, conversion of the resulting cyclic enone into an allylic enol carbonate, and Tsuji–Trost allylation using a chiral palladium complex. Very high levels of diastereocontrol, favoring the diastereomer in which there is a cis relationship
A Facile Synthesis of Hydroxamic Acids of<i>N<sup>α</sup></i>-Protected Amino Acids Employing BDMS, a Study of Their Molecular Docking and Their Antibacterial Activities
作者：K. Uma、H. S. Lalithamba、V. Chandramohan、K. Lingaraju
DOI：10.1080/00304948.2019.1579039
日期：2019.3.4
Hydroxamic acids have received much attention as biologically active compounds. Synthetic hydroxamic acids enhance the growth of plant sources and improve the soil quality, act as antibiotics, cell...
medium. Dimethylchloramine prepared in a pure state undergoes dehydrohalogenation in an alkaline medium: the principal products formed are N-methylmethanimine, 1,3,5-trimethylhexahydrotriazine, formaldehyde, and methylamine. The kinetics of this reaction was studied by UV, GC, and HPLC as a function of temperature, initial concentrations of sodium hydroxide, and chlorinated derivative. The reaction is of
PYRAZOLO[1,5a]PYRIMIDINE DERIVATIVES AS IRAK4 MODULATORS
申请人：Arora Nidhi
公开号：US20120015962A1
公开（公告）日：2012-01-19
Compounds of the formula I or II:
wherein X, m, Ar, R
1
and R
2
are as defined herein. The subject compounds are useful for treatment of IRAK-mediated conditions.
Compositions for Treatment of Cystic Fibrosis and Other Chronic Diseases
申请人：Vertex Pharmaceuticals Incorporated
公开号：US20150231142A1
公开（公告）日：2015-08-20
The present invention relates to pharmaceutical compositions comprising an inhibitor of epithelial sodium channel activity in combination with at least one ABC Transporter modulator compound of Formula A, Formula B, Formula C, or Formula D. The invention also relates to pharmaceutical formulations thereof, and to methods of using such compositions in the treatment of CFTR mediated diseases, particularly cystic fibrosis using the pharmaceutical combination compositions.
