Triclosan is prone to phase II metabolism via sulfotransferase and glucuronosyltransferase enzymes (Wang et al., 2004). In humans the resulting conjugates are excreted primarily in urine (Sandborgh-Englund et al., 2006).
Oral and dermal routes (humans and rodents): Triclosan absorbed from the gastrointestinal tract undergoes extensive first-pass metabolism, which primarily involves glucuronide and sulfate conjugation. In both humans and rodents, at high triclosan plasma concentrations, metabolism shifts from the generation of predominantly glucuronide conjugates to sulfate-conjugates. The bioavailability of unconjugated triclosan may be limited after oral exposure because of triclosan's extensive first-pass metabolism. Triclosan is also metabolized to its glucuronide and sulfate conjugates by the skin.
Triclosan has been widely used as a disinfectant in human health care products. Although this particular chemical is less toxic, its biotransformation products might have toxicity to human. Therefore, understanding the pharmacokinetics and metabolism of triclosan in animal and human body is important. Plasma samples from SD rats collected after the oral administration of 5 mg/kg triclosan were analyzed ... . The pharmacokinetic data of triclosan in the rats were presented including the half time of elimination that was (48.5 +/- 10.5) hr, indicating that the elimination of triclosan in the rat was slow. Two hydroxylated and sulfonated triclosan, one glucuronidated triclosan, and one sulfonated triclosan were identified in the rat plasma samples.
...Irgasan DP 300 is excreted unchanged in feces and urine (partly conjugated) but is also hydroxylated to five different monohydroxy metabolites which were found in urine; three of these were also present in feces.
Triclosan has known human metabolites that include Triclosan sulfate and (2S,3S,4S,5R)-6-[5-chloro-2-(2,4-dichlorophenoxy)phenoxy]-3,4,5-trihydroxyoxane-2-carboxylic acid.
IDENTIFICATION AND USE: Triclosan is a white to off-white crystalline powder. It is used as fungicide and bacteriostat. It is highly active against staphylococci and is used as an active agent in deodorants and antiseptic soaps. It is also used as material preservative for industrial and household plastics and textiles. HUMAN STUDIES: Fifty human subjects were treated with a 0.5% triclosan solution in a 1% soap solution. Triclosan was found not to be a sensitizer and the irritation potential depended on concentration. Tests also showed that triclosan was not a photosensitizing agent. Triclosan exposure might cause spontaneous abortion; probably through inhibition of estrogen sulfotransferase activity to produce placental thrombosis. In terms of estrogenic activity, triclosan displaced (3)H-estradiol from estrogen receptors (ER) of MCF7 human breast cancer cells and from recombinant human ER alpha/ER beta. In children, triclosan exposure was associated with allergic sensitization, especially inhalant and seasonal allergens, rather than food allergens. Current rhinitis was associated with the highest levels of triclosan, whereas no association was seen for current asthma. ANIMAL STUDIES: Triclosan was found to cause slight primary eye irritation when applied to the rabbit eye mucosa. Triclosan had a very low sensitization index in guinea pigs. Mice and rats administered triclosan intravenously at 10, 20 and 30 (rats only) mg/kg bw showed signs of slight cramps, exopthalmos (mice only), mydriasis (rats only), dyspnea, and ventral decubitus, with recovery by 24 to 48 hr after dosing. In an 18-month carcinogenicity bioassay in mice, 5 groups of male and female mice (70 mice/sex/dose) received triclosan in the diet at dose levels of 0, 10, 30, 100, or 200 mg/kg/day. Fifty mice/sex/dose received dietary triclosan for 18 months, while the remaining 20 mice/sex/dose received dietary triclosan for only 6 months, after which time these mice were sacrificed. After 18 months of exposure, a statistically significant increase in the incidence of hepatocellular adenoma and/or carcinoma was observed in male and female mice at 100 mg/kg/day triclosan and above. The incidence was dose-related in both sexes. In a developmental toxicity study in mice, triclosan was administered to 25 female mice/dose via the diet at target dose levels of 0, 10, 25, 75, or 350 mg/kg/day from days 6-15 of gestation. Maternal toxicity was observed at 75 mg/kg/day by increases in absolute and relative liver weight and tan areas in the liver of one dam. Developmental effects were noted at the 75 and 350 mg/kg/day target dose levels as increased incidence of variations (characterized as reversible irregular ossification of the skull at 75 and 350 mg/kg/day, and phalanges at 350 mg/kg/day). Decreased fetal weight was also observed 14 and 18% decrease at 75 and 350 mg/kg/day target dose levels, respectively). Triclosan decreased the synthesis of androgens followed by reduced sperm production in treated male rats. In rats, direct per oral pup exposure from postnatal day 3-16 to 50 or 150 mg triclosan/kg bw/day was performed. This exposure pointed to significant T4 reductions in 16 day old offspring in both dose groups. Triclosan was tested on Salmonella typhimurium strains TA1537, TA100, TA98, TA1535 and TA1538 with or without metabolic activation. There were no treatment-related increases in gene mutation at any dose. Dermal exposure to triclosan induces stimulation of the immune system in a murine model. ECOTOXICITY STUDIES: At environmentally relevant concentrations (<2 ug/L) it could cause a decline in the fish population. Triclosan in the aquatic environment may affect algal growth, chlorophyll synthesis, oxidative stress responses and cause biochemical alterations. Mature male western mosquitofish, Gambusia affinis, were exposed to triclosan concentrations of 100, 200, and 350 nM for 35 days. Vitellogenin mRNA expression was significantly elevated in the 350 nM triclosan treatment. Sperm counts in the same treatment group were significantly decreased. The mean hepatosomatic index in the 350 nM treatment group was significantly increased. This study demonstrates that triclosan has the potential to act as an endocrine disruptor in male mosquitofish. In the North American bullfrog, Rana catesbeiana, exposure to low levels of triclosan disrupts thyroid hormone-associated gene expression and can alter the rate of thyroid hormone-mediated postembryonic anuran development. Triclosan induced systemic toxic effects in C. elegans.
At in-use concentrations, triclosan acts as a biocide, with multiple cytoplasmic and membrane targets. At lower concentrations, however, triclosan appears bacteriostatic and is seen to target bacteria mainly by inhibiting fatty acid synthesis. Triclosan binds to bacterial enoyl-acyl carrier protein reductase enzyme (ENR), which is encoded by the gene FabI. This binding increases the enzyme's affinity for nicotinamide adenine dinucleotide (NAD+). This results in the formation of a stable ternary complex of ENR-NAD+-triclosan, which is unable to participate in fatty acid synthesis. Fatty acids are necessary for reproducing and building cell membranes. Humans do not have an ENR enzyme, and thus are not affected.
来源:Toxin and Toxin Target Database (T3DB)
毒理性
致癌性证据
癌症分类:尚未确定
Cancer Classification: Not Yet Determined
来源:Hazardous Substances Data Bank (HSDB)
毒理性
致癌物分类
对人类不具有致癌性(未被国际癌症研究机构IARC列名)。
No indication of carcinogenicity to humans (not listed by IARC).
A study conducted in 2000 demonstrated that low amounts of triclosan can be absorbed through skin and can enter the bloodstream. (A7866) Triclosan is rapidly absorbed and distributed in the human body (Sandborgh-Englund et al., 2006). Maximum concentrations are reached within three hours after oral intake. However, the metabolism and excretion of the compound is fast.
A study conducted in 2000 demonstrated that low amounts of triclosan can be absorbed through skin and can enter the bloodstream. [PMID: 10722890] Triclosan is rapidly absorbed and distributed in the human body (Sandborgh-Englund et al., 2006). Maximum concentrations are reached within three hours after oral intake. However, the metabolism and excretion of the compound is fast.
In one study, after in vivo topical application of a 64.5mM alcoholic solution of [(3)H]triclosan to rat skin, 12% radioactivity was recovered in the faeces, 8% in the carcass 1% in the urine, 30% in the stratum corneum and 26% was rinsed from the skin surface at 24 hours after application. [PMID: 10722890]
The number of personal hygiene products containing triclosan has increased rapidly during the last decade, and triclosan is one of the most common antibacterial compounds used in dentifrices today. However, the extent of triclosan exposure has not yet been well described. The potential risks of generating triclosan-resistant pathogenic microorganisms or of the selection of resistant strains are some areas of concern. The aim of the present study was to (1) obtain information on baseline levels of triclosan in plasma and urine, and (2) study the pharmacokinetic pattern of triclosan after a single-dose intake. Ten healthy volunteers were exposed to a single oral dose of 4 mg triclosan by swallowing an oral mouthwash solution. Triclosan in plasma and urine was followed before and up to 8 days after exposure. Triclosan levels in plasma increased rapidly, with a maximum concentration within 1 to 3 hr, and the terminal plasma half-life was 21 hr. The major fraction was excreted within the first 24 hr. The accumulated urinary excretion varied between the subjects, with 24 to 83% of the oral dose being excreted during the first 4 d after exposure. In conclusion, triclosan appears to be readily absorbed from the gastrointestinal tract and has a rapid turnover in humans. The high lipid solubility of the substance gives rise to questions regarding distribution properties and accumulation. The findings of the present study form a basis for greater understanding of the toxicokinetic properties of triclosan in humans.
/MILK/ Triclosan amounts in breast milk were reported to range from <20 to 300 ug/kg lipid in one study and <5 to 2100 ug/kg lipid in another. In a study that compared triclosan levels in women who used triclosan-containing products with those who did not, levels in breast milk were 0.022 to 0.95 ug/kg lipid compared to 0.018 to 0.35 ug/kg lipid, respectively.
Oral and dermal routes (humans and rodents): Triclosan glucuronide is predominantly excreted in the urine, and triclosan is predominantly excreted in the feces. Triclosan that is administered orally and dermally is excreted in greater concentrations in the urine than in the feces in humans, hamsters, rabbits, and monkey. In rats, mice, and dog, the reverse is true. Up to 87% of triclosan that is administered to humans (by an unspecified route) is excreted in the urine, most of it within 72 hr after dose.
2004年美国弗吉尼亚理工大学的一位老师(Dr. Peter Vikesland)在实验中发现,含有三氯生的产品与含氯的自来水反应后可生成一种被称为“哥罗芳”的物质——氯仿,即化学名为三氯甲烷。这种无色、易挥发且具特殊甜味的液体,在光照下会氧化生成氯化氢和甲醛。研究表明,小鼠口服LD50为4g/kg。
[EN] FUSED PYRAZOLE DERIVATIVES AS JAK INHIBITORS<br/>[FR] DÉRIVÉS DE PYRAZOLE CONDENSÉS UTILISÉS EN TANT QU'INHIBITEURS DE JAK
申请人:ALMIRALL SA
公开号:WO2017220431A1
公开(公告)日:2017-12-28
Novel fused pyrazole derivatives of Formula (I) are disclosed; as well as process for their preparation, pharmaceutical compositions comprising them and their use in therapy as inhibitors of Janus Kinases (JAK).
Catalytic Metal-free Allylic C–H Amination of Terpenoids
作者:Wei Pin Teh、Derek C. Obenschain、Blaise M. Black、Forrest E. Michael
DOI:10.1021/jacs.0c06997
日期:2020.9.30
selective replacement of C-H bonds in complex molecules, especially natural products like terpenoids, is a highly efficient way to introduce new functionality and/or couple fragments. Here, we report the development of a new metal-free allylic amination of alkenes that allows the introduction of a widerange of nitrogen functionality at the allylic position of alkenes with unique regioselectivity and no
POLYETHYLENE GLYCOL DERIVATIVES OF PALMITOYLETHANOLAMIDE AND ANALOGOUS ACYLETHANOLAMIDES
申请人:EPITECH GROUP S.r.l.
公开号:US20150157733A1
公开(公告)日:2015-06-11
The synthesis of a series of Polyethylene glycol conjugates (esters and carbonates) of PEA and its analogous acylethanolamides, have higher water solubility and good hydrophilic/lipophilic balance, resulting in (i) improved accumulation in tissues (particularly skin and mucosae), (ii) prolonged release, and (iii) increased bioavailability. Improvement of PEA and analogous acylethanolamides levels in the tissues—particularly in the skin and mucosae—and their prolonged release is due to the improved bioavailability of related conjugates. Conjugates are able to extend the time frame in which PEA and analogous acylethanolamides exert their pharmacological effects.
[EN] CYCLIC PEROXIDE OXIDATION OF AROMATIC COMPOUND PRODUCTION AND USE THEREOF<br/>[FR] OXYDATION DE PEROXYDE CYCLIQUE DE PRODUCTION DE COMPOSÉ AROMATIQUE ET SON UTILISATION
申请人:UNIV TEXAS
公开号:WO2014158209A1
公开(公告)日:2014-10-02
The present invention provides a method for converting an aromatic hydrocarbon to a phenol by providing an aromatic hydrocarbon comprising one or more aromatic C-H bonds and one or more activated C-H bonds in a solvent; adding a phthaloyl peroxide to the solvent; converting the phthaloyl peroxide to a di-radical; contacting the di-radical with the one or more aromatic C-H bonds; oxidizing selectively one of the one or more aromatic C-H bonds in preference to the one or more activated C-H bonds; adding a hydroxyl group to the one of the one or more aromatic C-H bonds to form one or more phenols; and purifying the one or more phenols.
Kappa agonist compounds and pharmaceutical formulations thereof
申请人:——
公开号:US20030144272A1
公开(公告)日:2003-07-31
Compounds having kappa opioid agonist activity, compositions containing them and method of using them as analgesics are provided.
The compounds of formulae I, II, IIA, III, IIIA, IIIB, IIIB-i, IV and IVA have the structure:
1
2
wherein
R
1
, R
2
, R
3
, R
4
; and
X, X
4
, X
5
, X
7
, X
9
;
Y, Z and n are as described in the specification.