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PubMedDate not supplied

[The provision of comfortable conditions while working with medical endoscopes and illuminators with halogen-filament lamps].

An analytical relationship has been established between the electric parameters of an illuminator and the lighting parameters and the service life of halogen lamps when operating on industrial mains power supplies. The paper shows a way of improving the above characteristics to provide comfortable working conditions and to enhance labour productivity by applying the constant power sources with the preset voltage stabilization factor. Plots of luminous flux instability and service life against voltage stabilization factor have been constructed from the derived formulas for a K[symbol see text]15-150 halogen filament. Recommendations are given to calculate a stabilization factor for a constant power source.

Endoscopes↗

PubMed1976

[Biotransformation of halogen anesthetics and liver toxicity].

The authors attempt to explain halothane-induced hepatitis by a mechanism involving direct toxicity of a metabolite of this halogen compound. This implies a genetically determined metabolic disturbance or an increase in metabolic rate through previous enzyme induction (repeated anesthesia with halogen compounds).

Anesthetics↗

PubMed1999

Halogenated phlorethols and fucophlorethols from the brown alga Cystophora retroflexa.

From an ethyl acetate fraction of the brown alga Cystophora retroflexa several halogenated phlorotannins were isolated. Most of the compounds are derivatives of diphlorethol penta-acetate and triphlorethol-A hepta-acetate. The majority turned out to be chlorinated and/or brominated. Only one iodinated substance, 2-iodophloroglucinol triacetate, was isolated. The structure of this derivative and the following compounds have been characterized previously: 2([D])-bromodiphlorethol penta-acetate, 3([A1])-bromodiphlorethol penta-acetate, 4([D])-bromo-diphlorethol penta-acetate, 4([D])-chlorodiphlorethol penta-acetate, 3([A1])-chlorotriphlorethol-A hepta-acetate, 4([D])-bromotriphlorethol-A hepta-acetate and 4([D])-chlorobisfucopentaphlorethol-A nonadeca-acetate. Ten halogenated phlorethols and two chlorinated fucophlorethols are described for the first time and characterized as their acetates: 2([B])-bromotriphlorethol-A hepta-acetate, 2([D])-bromotriphlorethol-A hepta-acetate, 2([B]), 2([D])-dibromotriphlorethol-A hepta-acetate, 3([A1]), 5([A1])-dichlorotriphlorethol-A hepta-acetate, 3([A1]), 4([D])-dichlorotriphlorethol-A hepta-acetate, 3([A1])-chloro-4([D])-bromotriphlorethol-A hepta-acetate. 2([B]), 4([D])-dichlorotriphlorethol-A hepta-acetate, 2([D]), 3([A1])-dibromotriphlorethol-A hepta-acetate, 3([A1])-bromo-2([D])-chlorotriphlorethol-A hepta-acetate, 2([D])-bromotetraphlorethol-C nona-acetate, 4([D])-chlorofucotriphlorethol-B dodeca-acetate and 4([D])-chlorobisfucotetraphlorethol-A heptadeca-acetate.

Chromatography, High Pressure Liquid↗

PubMed2000

Ultraviolet-induced detection of halogenated pyrimidines: simultaneous analysis of DNA replication and cellular markers.

BACKGROUND: We describe a new nonenzymatic methodology that allows the simultaneous detection of DNA replication and other cellular markers such as immunophenotyping. DNA replicating cells are identified by their incorporation of halogenated thymidine analogs, e.g., 5-bromo-deoxyuridine (BrdUrd). METHODS: Irradiation with ultraviolet (UV)-B or UV-A light in the presence of Hoechst 33258 and subsequent treatment with a hypotonic buffer makes BrdUrd accessible to monoclonal antibodies (mAb), thus allowing its sensitive detection. RESULTS: The photolysis of BrdUrd in DNA with UV light is sequence dependent and results in DNA damage, allowing the detection of remaining BrdUrd using hypotonic conditions. However, treatment with other inducers of single or double- strand breaks of DNA such as gamma irradiation or hydrogen peroxide did not allow BrdUrd detection. The new methodology is compatible with both mild crosslinking fixation, i.e., aldehydes, or coagulative fixation, i.e., alcohols. The successful identification of CD34+, CD138+, or CD19+ cells out of heterogeneous cell suspensions and their cell-cycle analysis are described. Results correlated very well with acid denaturation (r = 0.972). The average coefficient of variation (CV) of G(1) in the DNA histogram was smaller than 5%, resulting in good preservation of DNA distribution. Also, the signal-to-noise ratio was almost twice as high as for 2N acid denaturation, facilitating convenient discrimination of BrdUrd-positive cells. CONCLUSIONS: In contrast to previous approaches, this methodology eliminates the need for any additional enzymatic treatment such as DNA digestion or strand-break labeling after UV irradiation. The method is fast, convenient, and inexpensive and should be able to promote the use of halogenated pyrimidines in basic and clinical research of cancer, immunology, and pharmacology.

Antigens, CD19↗

PubMed2004

Electrostatic surface potential calculation on several new halogenated benzimidazole-like dopaminergic ligands.

We examined the effects of the electron density distribution (electrostatic surface potential; ESP) of several new benzimidazole-type ligands on their binding affinity for the D(1) and D(2) dopamine receptors (DAR). Receptors were prepared from synaptosomal membranes of bovine caudate nuclei. [(3)H]SCH 23390 and [(3)H]spiperone were used as specific radiolabels for the D(1) and D(2) receptors, respectively. The ESP of these compounds was calculated using Gaussian 98 W software. Calculations performed with known dopaminergic ligands showed that the electron density charge in the aromatic ring of these compounds favors a higher binding affinity for the D(2) DAR. This was confirmed by the synthesis of halogenated analogues of several known dopaminergic ligands. Halogenation resulted in an increase in the positive charge of the aromatic part of the molecule. None of the newly synthesized compounds was efficient in displacing [(3)H]SCH 23390 from the D1 DAR. The introduction of chlorine into the molecule led to a higher binding affinity for the D(2) DAR of the new ligands in comparison to both parent compounds and brominated ligands. This difference probably originates from the difference in the sizes of chlorine and bromine atoms, which could influence the interaction of a ligand with the receptor binding site. However, among the new ligands with bromine as a substituent, two compounds (8b and 10b) expressed a higher binding affinity and two of them (9b and 11b) a lower binding affinity for the D(2) DAR, when compared to unsubstituted parent compounds. These results indicate that the electrostatic surface potential of a ligand is an important factor in its interaction with the D(2) DAR and that this should be taken into account during design and synthesis of dopaminergic compounds.

Animals↗

PubMed2005

An experimental and computational study on the effect of Al(OiPr)3 on atom-transfer radical polymerization and on the catalyst-dormant-chain halogen exchange.

Compound Al(OiPr)3 is shown to catalyze the halide-exchange process leading from [Mo(Cp)Cl2(iPrN=CH-CH=NiPr)] and CH3CH(X)COOEt (X=Br, I) to the mixed-halide complexes [Mo(Cp)ClX(iPrN=CH-CH=NiPr)]. On the other hand, no significant acceleration is observed for the related exchange between [MoX3(PMe3)3] (X=Cl, I) and PhCH(Br)CH3, by analogy to a previous report dealing with the Ru(II) complex [RuCl2(PPh3)3]. A DFT computation study, carried out on the model complexes [Mo(Cp)Cl2(PH3)2], [MoCl3(PH3)3], and [RuCl2(PH3)3], and on the model initiators CH3CH(Cl)COOCH3, CH3Cl, and CH3Br, reveals that the 16-electron Ru(II) complex is able to coordinate the organic halide RX in a slightly exothermic process to yield saturated, diamagnetic [RuCl2(PH3)3(RX)] adducts. The 15-electron [MoCl3(PH3)3] complex is equally capable of forming an adduct, that is, the 17-electron [MoCl3(PH3)3(CH3Cl)] complex with a spin doublet configuration, although the process is endothermic, because it requires an energetically costly electron-pairing process. The interaction between the 17-electron [Mo(Cp)Cl2(PH3)2] complex and CH3Cl, on the other hand, is repulsive and does not lead to a stable 19-electron adduct. The [RuCl2(PH3)3(CH3X)] system leads to an isomeric complex [RuClX(PH3)3(CH3Cl)] by internal nucleophilic substitution at the carbon atom. The transition state of this process for X=Cl (degenerate exchange) is located at lower energy than the transition state required for halogen-atom transfer leading to [RuCl3(PH3)3] and the free radical CH3. On the basis of these results, the uncatalyzed halide exchange is interpreted as the result of a competitive S(N)i process, whose feasibility depends on the electronic configuration of the transition-metal complex. The catalytic action of Al(OiPr)3 on atom-transfer radical polymerization (and on halide exchange for the 17-electron half-sandwich Mo(III) complex) results from a more favorable Lewis acid-base interaction with the oxidized metal complex, in which the transferred halogen atom is bound to a more electropositive element. This conclusion derives from DFT studies of the model [Al(OCH3)3]n (n=1,2,3,4) compounds, and on the interaction of Al(OCH3)3 with CH3Cl and with the [Mo(Cp)Cl3(PH3)2] and [RuCl3(PH3)3] complexes.

Journal Article↗

PubMed2007

Self-assembly of halogenated cobaltacarborane compounds: boron-assisted C--H...X--B hydrogen bonds?

Full structural characterisation and complete synthetic procedures for three monohalogenated cobaltacarborane compounds closo-[3-Co(eta5-C5H5)-8-X-1,2-C2B9H10] (X=Cl (1), Br (2), I (3)) and the dibromo derivative closo-[3-Co(eta5-C5H5)-8,9-Br2-1,2-C2B9H9] (4) are reported. The supramolecular structures of 1, 3, and 4 reveal the existence of intermolecular C--HX--B interactions. The role of these interactions has been investigated through a CSD search and subsequent analysis of the reported crystalline compounds. The results show that halogens become reasonably good hydrogen-bond acceptors when bonded to boron and, in this respect, are comparable in strength to metal-bound halogens.

Boron↗

PubMed1994

Unspecific degradation of halogenated phenols by the soil fungus Penicillium frequentans Bi 7/2.

Resting phenol-grown mycelia of the fungus Penicillium frequentans strain Bi 7/2 were shown to be capable of metabolizing various monohalogenated phenols as well as 3,4-dichlorophenol. 2,4.dichlorophenol could be metabolized in the presence of phenol as cosubstrate. In the first degradation step the halogenated phenols were oxidized to the corresponding halocatechols. Halocatechols substituted in para-position (4-halocatechols) were further degraded under formation of 4-carboxymethylenbut-2-en-4-olide. A partial dehalogenation took place splitting the ring system. 3-Halocatechols were cleaved to 2-halomuconic acids as dead end metabolites without a dehalogenation step. Dichlorophenols were only transformed to the corresponding catechols. In addition 3,5-dichloro-catechol was O-methylated to give two isomers of dichloroguiacol. The halogenated catechols with the exception of 4-fluorocatechol partly polymerized oxidatively in the culture fluid to form insoluble dark-brown products. The degradation of halophenols are due to the action of unspecific intracellular enzymes responsible for phenol catabolism (phenol hydroxylase, catechol-1,2-dioxygenase, muconate cycloisomerase I).

Biodegradation, Environmental↗

PubMed1978

Mechanism of hydrolysis of halogenated nitrosoureas.

The hydrolysis kinetics of halogenated nitrosoureas were investigated using chlorozotocin as a model. Evidence is presented to show that the hydrolytic reaction of halogenated nitrosoureas between pH 3 and 8 is a summation of spontaneous water and hydroxide-ion-catalyzed reactions; the later reaction is the sum of two parallel reactions. The relative contribuiton of each reaction changes with pH and results in different product distributions. Dianionic phosphate (HPO42-) increased the amount of free chloride-ion production without significantly altering the hydrolysis rate. A mechanism is proposed to explain this behavior. The role of hydrolytic decomposition products produced at physiological pH on the biological activity of nitrosoureas is discussed.

Chlorides↗

PubMed2001

Violation of frozen shell approximation in dissociative electron capture by halogenated anthraquinones.

A series of halogenated anthraquinone (AQ) derivatives has been studied by means of electron capture negative ion (NI) mass spectrometry (ECNI-MS). 1Cl-AQ and 2Br-AQ display dramatically steep positive temperature dependencies of Hal(-) ion abundance in the low electron energy region. Molecular NI intensity decreases rapidly with increasing temperature in the case of 1I-AQ. In the case of 2Br-AQ, a metastable NI peak (m/z 22.9) corresponding to the process BrAQ(-) --> Br(-) + AQ(0) was recorded. This means that the characteristic dissociation lifetime of the molecular NI Br-AQ(-) is at least approximately 25 micros at the energy approximately 0.67 eV in the low-temperature spectrum (T approximately 80 degrees C), and at the energy approximately 0.13 eV in the hot spectrum (T approximately 290 degrees C). Together with the observed temperature dependence of the 2Br-AQ curves of effective yield (CEY), this proves that this anion dissociates according to Coulson's model. The same halogen anion behavior is observed in the case of 1Cl-AQ. There are three consecutive stages in the process of molecular NI dissociation of Cl- and Br-substituted AQ, namely, electron capture into the empty pi-orbital by means of the shape resonance mechanism, followed by a radiationless transition into the ground electronic pi-state of the anion, as predicted by Compton in the case of the parabenzoquinone molecule, and, finally, a fluctuative dissociation of the molecular NI accompanied by the transition from the pi-term into the sigma-term, so-called predissociation. Calculations show reasonable agreement with the experimental data. In the case of 1I-AQ, an effect of inversion of empty levels in the process of electron capture by the molecule takes place, a violation of the so-called frozen shell approximation. The phenomenon found may be of significance not only in the case of ECNI-MS, but also in other experimental investigations using low-energy electron-molecule and ion-molecule collisions.

Anthraquinones↗

PubMed1986

Comparative carcinogenicity of ring-halogenated 3-methyl-1-phenyltriazenes and their 3,3-dimethyl analogs at equimolar dose levels in male Sprague-Dawley rats.

The carcinogenic activity of 3-methyl-1-phenyltriazene and its four 4- and 2-ring halogenated derivatives was similar to the previously reported carcinogenicity of the corresponding 3,3-dimethyl-1-phenyltriazene analogs tested at equimolar dose levels in adult male Sprague-Dawley rats. The strongest carcinogens in each series were 3-methyl-1-phenyltriazene and 3,3-dimethyl-1-phenyltriazene, respectively. The carcinogenic potency of the individual test compounds decreased with progressive 4- and 2-halogenation of the phenyl ring. The administration of either 3-methyl-1-(2,4,6-trichlorophenyl)- or 3-methyl-1-(2,4,6-tribromophenyl)-triazene gave a negligible tumor yield not different from that observed in the control animals. Moreover, 3,5-dichloro-2-(3,3-dimethyl-1-triazeno)-benzoic acid or its ethyl ester, were found to be strong carcinogens that exclusively induced kidney tumors.

Animals↗

PubMed1996

The influence of selected metals and halogens on the electronic system of benzoic acid.

The influence of halogens and metals on the electronic system of the aromatic ring in lithium, sodium and potassium complexes with p-halogenobenzoic acids has been investigated by means of (13)C and (1)H NMR, IR and Raman spectroscopy and semi-empirical calculations. It has been shown that ionic potentials and electronegativities of halogens and metals are the main factors responsible for perturbations of the electronic charge distribution in the ring.

Journal Article↗

PubMed2005

Biological activity and physicochemical parameters of marine halogenated natural products 2,3,3',4,4',5,5'-heptachloro-1'-methyl-1,2'-bipyrrole and 2,4,6-tribromoanisole.

Physicochemical parameters (vapor pressure, water solubility, Henry's law constant) and biological activities of two halogenated natural products frequently detected in marine samples and food were determined. Synthetic 2,3,3',4,4',5,5'-heptachloro-1'-methyl-1,2'-bipyrrole (Q1) and 2,4,6-tribromoanisole (TBA) were available in pure form. The physicochemical parameters were in the range of anthropogenic chlorinated compounds of concern. The aqueous solubilities at 25 degrees C (S(w,25)) of Q1 and TBA were 4.6 microg/L and 12,200 microg/L, respectively, whereas subcooled liquid vapor pressures were 0.00168 Pa (Q1) and 0.06562 Pa (TBA) as measured by the gas chromatographic-retention time technique. Q1 was negative by established test systems for the determination of ethoxyresorufin-O-deethylase (EROD) induction and by sulforhodamine B assay. EROD induction potency was at least 10(-7) times lower than that of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). At a relatively high concentration (20 microM), Q1 inhibited specific binding of 2 nM [(3)H]TCDD to the in vitro-expressed human aryl hydrocarbon receptor (AHR) by 18%; lower concentrations showed no effect. Molecular modeling showed that Q1 is nonplanar, consistent with its relatively modest affinity as an AHR ligand. When tested for cell-growth inhibitory/cytocidal activity in human tumor cells, Q1 was only marginally, if at all, active with an IC(50) value >50 microM compared with five to ten times lower IC(50) values for potent cytotoxins tested in the test system used. Furthermore, standard pesticide tests on insecticidal, herbicidal, and fungicidal activity did not provide any significant activity at highest concentrations. For TBA, the results in all tests were comparable with Q1. The SRB assay was also applied to the halogenated natural product 4,6-dibromo-2-(2',4'-dibromo)phenoxyanisole, but no toxic response was found. Although it was apparent that Q1 and TBA had been proven to have relatively low biological activity in all tests performed, further research is necessary to clarify whether metabolites of the compounds eventually may possess a risk to humans or other living organisms. Nevertheless, the role of Q1 in nature remains uncertain.

Animals↗

PubMed1988

The central nervous stimulating effect of four different halogenated ether anesthetics and halothane in mice.

Although enflurane is a convulsive anesthetic, its structural isomer, isoflurane, is believed not to be. We reported previously that, unexpectedly, isoflurane more frequently produced opisthotonus in young mice, especially during the induction period, than enflurane. In the present study, we examined the incidences of opisthotonus induced by four halogenated ether anesthetics and halothane to evaluate their CNS stimulating actions. As experimental animals, we used young male mice, with another two aged groups of male mice to clarify the relationship of the incidence of opisthotonus to aging. The percentage incidence of opisthotonus was 93% for sevoflurane, 81% for isoflurane, 64% for enflurane, 17% for methoxyflurane and 2% for halothane. These results suggest that the halogenated ether anesthetic, which is rapidly uptaken by the CNS during induction, is more likely to produce CNS stimulation, subsequently leading to opisthotonus. There was no age related susceptibility difference to anesthetic-induced opisthotonus, except for enflurane, in which the incidence of opisthotonus was higher in the aged group.

Journal Article↗

PubMed1988

Determination of peroxidative halogenation in mixtures of chloride and bromide.

A method for the differentiation of chlorinated and brominated products from peroxidative oxidation of mixtures of the halides is presented. Chlorination or bromination of monochlorodimedone (MCD) by fungal chloroperoxidase (CPO) was measured by loss of MCD absorbance. Although the Vmax was similar for both halides [approximately 0.08 mM (2 min)-1], the apparent Km for chlorination was 10 times greater than that for bromination (5.88 vs 0.67 mM). Chlorination was also quantitated as I3- produced from N-chlorotaurine and I-. The Vmax [0.076 mM (2 min)-1] and apparent Km (6.31 mM) determined by this method agreed with those determined with MCD. Selective reduction by H2O2 of the I-oxidizing potential of N-bromotaurine allowed determination of the brominated product from the difference between the amounts of halogenated MCD and N-chlorotaurine. The brominated product predominated at saturating and at physiologic halide levels. Hence, it is suggested that Br- plays a significant role in halogenation even though in vivo levels of Cl- are equal to or greater than 1000 times those Br-.

Bromides↗

PubMed1983

Competitive binding to the cytosolic 2,3,7,8-tetrachlorodibenzo-p-dioxin receptor. Effects of structure on the affinities of substituted halogenated biphenyls--a QSAR analysis.

The proposed mechanism of action of the toxic halogenated aromatics, typified by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), involves the initial binding to a high-affinity, low-capacity, cytosolic receptor protein. Previous studies have shown that several 4'-halo-2,3,4,5-tetrachlorobiphenyls bind to the TCDD receptor and that a lateral substituent on both phenyl rings is required for activity. Using an extended series of eighteen 4'-substituted-2,3,4,5-tetrachlorobiphenyls as probes, the effects of a variable lateral substituent on receptor binding affinity and the induction of aryl hydrocarbon hydroxylase (AHH) in vivo and in rat hepatoma H-4-II E cells have been determined. For most substituents, there was an excellent correlation between the rank-order potency for receptor binding and the rank-order potency for AHH induction. Based on in vitro binding affinities (EC50 values) of the 4'-substituted tetrachlorobiphenyls, a multiparameter regression equation was formulated correlating the binding constants to physicochemical substituent parameters. For thirteen compounds out of the present series, multiple regression analysis of the binding data led to the following equation: log(1/EC50) = 1.53 sigma + 1.47 pi + 1.09HB + 4.08, r = 0.978. The results suggest that halogen substitution on both phenyl rings is not a requirement for binding and that hydrophobic (pi) and electronic (sigma) substituent constants and a variable for hydrogen bond (HB) formation are significant parameters describing relative binding avidities of this series of substituted biphenyls for the TCDD receptor.

Animals↗

PubMed1981

Structure-activity relationships in halogenated biphenyls: unifying hypothesis for structural specificity.

Using chlorinated biphenyls as model halogenated aromatic hydrocarbons, in this and previous work we have investigated the specific structural requirements for induction of cytochrome P-448, P-450 and associated monooxygenase activities, and exquisite toxicity in the guinea pig. The requirement of planarity of coplanarity was examined using single crystal X-ray techniques to describe the structure and conformation of PCBs and PBs in the solid state as an approximation of their interactions with a bioreceptor. It was concluded that the most stable conformation of all biphenyls with or without ortho-substitutents is non-planar and that neigher planarity nor symmetry is an inherent requirement for receptor binding. The basic requirement for toxic structures was the availability of at least three lateral bromines or four lateral chlorines arranged in about a 3 X 10 A triangle or box, respectively. The underlying factor in the apparent symmetry requirement (as determined by the number and positions of halogens) is net polarizability of the molecule. Sufficient polarization for binding requires four lateral chlorines or three lateral bromines. Planarity or coplanarity of rings is necessary only to effect juxtaposition of the four lateral chlorines, and binding is therefore facilitated by an increased population of planar conformers. The population of planar conformers in biphenyls is in turn reduced by the degree of ortho substitution and hindrance to rotation about the pivot bond. Net polarizability is increased by the buttressing effect of adjacent chlorines or bromines, especially when ortho positions are involved. Coplanarity effects steric fit to the receptor while polarizability effects binding affinity. Excessive buttressing may lower binding affinity. Some variation in these properties through molecular conformational preferences in the biphenyls is thought to explain the apparent 'mixed induction' seen for certain isomers. This is a unifying hypothesis for structural specificity based on the available and definitive crystallographic, theoretical and toxicological data on these pure compounds.

Biphenyl Compounds↗

PubMed1996

Pharmacological activities of trimetoquinol and 1-benzyl halogen-substituted analogues on rat beta-adrenoceptor subtypes.

The beta-adrenoceptor activity profile of trimetoquinol and its 1-benzyl halogen-substituted analogues was studied in rat tissues containing primarily beta 1 (atria)-, beta 2 (trachea)- and atypical beta/beta 3 (distal colon and brown adipose tissue)-adrenoceptors. Functional biological activity resided in the (-)-isomer of trimetoquinol which was 112-, 275-, 372- and 513-fold more potent than (+)-trimetoquinol in trachea, right atria, distal colon and brown adipose tissue, respectively. (+/-)-Trimetoquinol was equally or slightly less active than (-)-trimetoquinol. The 1-benzyl halogen-substituted analogues of trimetoquinol exhibited differential activation of beta-adrenoceptor subtypes. In functional assays, 3'-iodotrimetoquinol was a potent activator of all beta-adrenoceptor subtypes. 3',5'-Diiodotrimetoquinol was 10-fold more potent as an agonist in tissues containing atypical beta/beta 3-adrenoceptors than those tissues containing beta 1- and beta 2-adrenoceptor sites. Furthermore, this drug was a partial agonist as compared to (+/-)-trimetoquinol and 3'-iodotrimetoquinol on beta 1-adrenoceptors. Pharmacological properties of the compounds on rat beta 3-adrenoceptors expressed in Chinese hamster ovary (CHO) cells were consistent with results observed in functional assays. 3',5'-Diiodotrimetoquinol possessed the greatest potency for activation of adenylyl cyclase. Rank order of affinity for rat beta 3-adrenoceptor was 3'-iodotrimetoquinol = 3',5'-diiodotrimetoquinol > (+/-)-trimetoquinol > (-)-isoprenaline. These results suggest that 3',5'-diiodotrimetoquinol is a promising drug for further chemical modification in the development of selective beta 3-adrenoceptor ligands.

Adipose Tissue, Brown↗