Dimethyl sulfoxide, inhibition

Navas, III M.A.A., Ding, J.L., Ho, B. Inactivation of Factor C by dimethyl sulfoxide inhibits coagulation of the Carcinoscorpius amoebocyte lysate. Biochem Inti 21 (1990) 805-813. 

In two animal studies methylcobalamin or dimethyl-sulfoxide inhibited the ototoxic adverse effects of gentamicin (13,14). 

Forskolin activation of adenylate cyclase can be inhibited by high concentrations of detergents and low molecular weight alcohols. Inhibition of forskolin stimulated adenylate cyclase by ethanol can be observed at 0.2M and results in 50% Inhibition at l.OM. Butanol and propanol are more effective at Inhibiting forskolin stimulated adenylate cyclase than ethanol. Dimethyl sulfoxide inhibits the stimulation of adenylate cyclase by forskolin much less than ethanol. 5... 

When electron-withdrawing groups are attached to the double bond, the reaction is strongly inhibited and may fail completely. In such cases, the bromide anion, produced by the reaction of dimethyl sulfoxide with N-bromosuccinimide, competes with the dimethyl sulfoxide for the bromonium (or bromo carbonium) ion, an intermediate of the reaction. Thus, dibromide may accompany recovered alkene or any bromohydrin formed. Similarly, exogenous anions often compete with dimethyl sulfoxide for the cation. ... 

Rapid-acting dermally hazardous cytotoxin that inhibits protein synthesis and affects clotting factors in the blood. It is capable of producing incapacitating or lethal effects. T2 is obtained from various molds and fungi (Fusarium sp.). It is a colorless crystalline solid of white powder that melts at 304°F. Impure samples may be a colorless to slightly yellow oil. It is slightly soluble in water, but soluble in ethyl acetate, acetone, ethanol, chloroform, methylene chloride, diethyl ether, and dimethyl sulfoxide (DMSO). It is heat stable and can be stored at room temperature for years. 

Topical diclofenac in a dimethyl sulfoxide carrier (Pennsaid) is a safe and effective treatment for OA pain. It is thought to act primarily by local inhibition of COX-2 enzymes. The product was under review by the U.S. FDA at the time of this writing. 

The tyrosine kinase inhibitors genistein [4—50pM dissolved in 0.05% dimethyl sulfoxide (DMSO), 30 minutes] and herbimycin (500 pM dissolved in 0.05%i DMSO, 30 minutes) are described as being useful inhibitors of caveolae uptake (61,62), which can be applied to discriminate this pathway from clathrin-mediated uptake (63). It should be questioned if a block of the enzyme affects the uptake via caveolae uptake selectively. However, genistein is thought to inhibit the receptor-induced formation of caveolae (18). As for herbimycin, no comment can be given on its selectivity. 

Figure 3. Kinetics of conq)etitivc inhibition of Clostridium thermohydrosuljur-icum strain 39E purified amylopuUulanase activity with mixed substrates. The solid lines A and C indicate the theoretical plots for competitive inhibition at amylose ccmcentrations of 0.6 and 2.4 mg/ml, respectively. Lines B and D are the theoretical plots for the absence of inhibition at the same respective amylose ccmcentrations. PuUulan was used at concentrations of 0.4, 0.8, 1.2, 1.6, 2.0, 2.4 mg/ml. For clarity, only two sets of data points were used in the above plot. ( ) and (A) are the practical data points obtained at 0.6 and 2.4 mg/ml amylose concentrations. All reaction mixtures contained 5% (v/v) dimethyl sulfoxide for solubility of amylose. [S] = [A] + [P], where S is the total substrate ccmcentration. A and P are the concentrations of amylose and pullulan, respectively. (Reproduced with permissiem from Ref. 13. Copyright 1990 Academic Press, Inc.)...

Drug Treatment for Inhibition of Tumor Cell Migration 1. Drug or inhibitor to be tested. Here we use cisplatin cis-diammineplatinum(ll) dichloride), stored in aliquots of 100 mM in dimethyl sulfoxide (DMSO) at -20°C for up to 4 weeks. 2. DMSO or appropriate solvent for the agent under test. 

Other electrochemical processes of organic compounds on Pb electrodes or electrodes with UPD Pb have been studied - formaldehyde [323], oxalic acid [386], trichloro- and trifluoroethane [387], 1-phenylethylamine [388], 3-hydroxychi-nuclidine [388], dichlorodifluoromethane [389], polychlorobenzenes [390], 1-propa-nol [391], pyrrole polymerization [392], and inorganic compounds - phosphine [388] and sulfate(IV) ions [393]. Simultaneous catalytic or inhibiting influence of organic solvents - acetonitrile, dimethyl-sulfoxide, and Pb + presence on electrooxidation of small organic molecules on Pt electrodes has been studied using on-line mass spectroscopy [394],... 

Divinyl DMDT DMF DMS DMSO DNT DOA 1-Dodecanethiol Dodecanol Dodecanol Dodecanol Peroxide Dodecene 1-Dodecene Dodecene (Non-Linear) Dodecene (Non-Linear) Dodecyl Alcohol Dodecylbenzene Butadiene, Inhibited Methoxychlor Dimethylfbrmamide Dimethyl Sulfide Dimethyl Sulfoxide 2,4-Dinitrotoluene Dioctyl Adipate Lauryl Mercaptan Linear Alcohols (12-15 Carbons) Dodecanol Lauroyl Peroxide Dodecene 1-Dodecene Propylene Tetramer Dodecene Dodecanol Dodecylbenzene... 

Phenanthroline in the presence of heavy metals acts as an activator of the polymerization of vinyl compounds558,559 and other olefins.560-564 It also assists the dimerization of olefins in the presence of titanium catalysts.565,566 It enhances the metal catalyzed oxidation of ascorbic acid567 and dimethyl sulfoxide.568 On the other hand, on its own it can inhibit several polymerization processes.545,569 It also stabilizes butadiene and isoprene and prevents their dimerization.570 It prevents peroxide formation in ether,571 inhibits the vinylation of alcohol572 and stabilizes cumyl chloride.573 It accelerates the vulcanization of diene rubbers574 and copolymers.575 1,10-Phenanthroline catalyzes the autooxidation of linoleic and ascorbic acids in the absence of metals.567... 

In 1992, Crabtree and co-workers reported the first nickel catalyst effective for silane alcoholysis.161 The complex, [Ni(tss)]2 (tss = salicylaldehyde thiosemicarbazone), bears a ligand that contains O and N donor groups and a semicarbazide sulfur. Alcoholysis of Et3SiH with ethanol or methanol occurs at room temperature in 50% dimethyl sulfoxide-benzene. However, the reaction is inhibited in the presence of strong donor ligands, H2, or atmospheric pressure of CO. 

For the highly inhibitive compounds in the TPA-induced inflammatory assay, we evaluated their antitumor-promoting activity by a standard initiation-promotion protocol [Fig. (3)] [37,40]. Initiation was achieved by a single application of 50 pg of DMBA (2), a well known tumor initiator, to the skin of backs of 8-week-old female ICR mice. From one week after initiation, 1 pg of TPA (1) was applied twice a week until week 20. The test compound (2.0 or 0.2 pM) dissolved in acetone-dimethyl sulfoxide (DMSO) (9 1, 100 pi) was applied 30 min before each TPA treatment. Groups of 15 mice were used. The number of tumors was counted weekly. 

It was shown <1999BML3255> that a crystalline ozonide obtained by ozonolysis of the A-allylamidc of Cbz-L-phenylalanine inhibits papain, a cysteine protease. Reduction of that ozonide in excess dimethyl sulfoxide (DMSO) generates in situ a peptide aldehyde, as proved by coupling with a stabilized Wittig ylide forming thereby an unsaturated ester. 

Tirzina Q) found that alkali lignin retarded the polymerization of styrene in dimethyl sulfoxide and strongly inhibited polymerization in the presence of oxygen and benzoyl peroxide. 

Table 2 also indicates that the nucleophiles effective for vinyl ethers are relatively mild, when compared with those for isobutene (cf., Section V.B.2). In fact, stronger bases lead to inhibition or severe retardation of polymerization [36,64] ketones aldehydes, amides, acid anhydrides, dimethyl sulfoxide (retardation) alcohols, aliphatic amines, pyridine (inhibition). The choice of nucleophiles is determined by their Lewis basicity (as measured by pKb, etc. [64,103]), and this factor determines the effic-tive concentrations of the nucleophiles. For example, the required amounts of esters and ethers decrease in the order of increasing basicity (i.e., a stronger base is more effective and therefore less is needed) [101,103] tetrahydrofuran < 1,4-dioxane ethyl acetate < diethyl ether. On the other hand, for amines not only basicity but also steric factors play an important role [142] thus, unsubstituted pyridine is an inhibitor, while 2,5-dimethylpyridine is an effective nucleophile for controlled/living polymerization, although the latter is more Lewis basic. 

Orr (43) used dimethyl sulfoxide as a free radical sink to inhibit the effect of Cu and ascorbic acid on catalase and 8-glucuronidase as well as the degradation of hyaluronic acid. The formation of a radical from ascorbic acid and Cu in water was detected by EPR (44). Based on an EPR spectroscopic study of ascorbic acid during oxidation of methyl-arachidonate-enriched liposomes, ascorbic acid may be important in preventing free radical damage in the central nervous system (45). 

Lipophylic inhibitors should be dissolved in dimethyl sulfoxide (DMSO). To avoid precipitation in the aqueous (polar) reaction mixture and to avoid different DMSO concentrations in the reaction mixture depending on the inhibitor concentration present, it is highly advisable to keep the DMSO concentrations constant in all reaction tubes, including the control tubes without inhibitor. DMSO may inhibit the RT reaction at varying degrees, depending on the nature of the RT enzyme. Ten percent DMSO is probably the maximum concentration that should be present in the reaction mixture (it may inhibit up to 50% of the reaction). It has been observed that lower concentrations of DMSO can even stimulate the RT reaction ... 

---