Kinetics of the aqueous periodate oxidation of aliphatic disulfides and thioethers

Evans, Brian J.; Doi, Joyce Takahashi; Musker, W. Kenneth

doi:10.1021/jo00296a009

Cited by 22 publications

(14 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…After removal of the 5Ј-DMT protecting group, the linker was coupled to the support-bound oligonucleotide by a modification of the procedure of Erlanson, Chen, and Verdine (15). The support-bound oligonucleotide was treated with a combination of 45 mg (178 mol) of 3,3Ј-dithiobis(propylamine) dihydrochloride (17), which was prepared as described for the 4-carbon homolog (12), 60 l (600 mol) of triethylamine, and 100 l of H 2 O for 16 h at room temperature. In the course of preparing O 6 -(2-p-nitrophenylethyl)-2-fluoro-2Ј-deoxyinosine, we observed cleavage of the nitrophenylethyl protecting group in the presence of wet tert-butyl ammonium fluoride.…”

Section: Gly Pro Glumentioning

confidence: 99%

Cross-Linking of the Fingers Subdomain of Human Immunodeficiency Virus Type 1 Reverse Transcriptase to Template-Primer

Peletskaya

Boyer²,

Kogon³

et al. 2001

J Virol

View full text Add to dashboard Cite

Cross-linking experiments were performed with human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) mutants with unique cysteine residues at several positions (positions 65, 67, 70, and 74) in the fingers subdomain of the p66 subunit. Two approaches were used-photoaffinity cross-linking and disulfide chemical cross-linking (using an oligonucleotide that contained an N 2 -modified dG with a reactive thiol group). In the former case, cross-linking can occur to any nucleotide in either DNA strand, and in the latter case, a specific cross-link is produced between the template and the enzyme. Neither the introduction of the unique cysteine residues into the fingers nor the modification of these residues with photocross-linking reagents caused a significant decrease in the enzymatic activities of RT. We were able to use this model system to investigate interactions between specific points on the fingers domain of RT and double-stranded DNA (dsDNA). Photoaffinity cross-linking of the template to the modified RTs with Cys residues in positions 65, 67, 70, and 74 of the fingers domain of the p66 subunit was relatively efficient. Azide-modified Cys residues produced 10 to 25% cross-linking, whereas diazirine modified residues produced 5 to 8% cross-linking. Disulfide cross-linking yields were up to 90%. All of the modified RTs preferentially photocross-linked to the 5 extended template strand of the dsDNA template-primer substrate. The preferred sites of interactions were on the extended template, 5 to 7 bases beyond the polymerase active site. HIV-1 RT is quite flexible. There are conformational changes associated with substrate binding. Cross-linking was used to detect intramolecular movements associated with binding of the incoming deoxynucleoside triphosphate (dNTP). Binding an incoming dNTP at the polymerase active site decreases the efficiency of cross-linking, but causes only modest changes in the preferred positions of cross-linking. This suggests that the interactions between the fingers of p66 and the extended template involve the "open" configuration of the enzyme with the fingers away from the active site rather than the closed configuration with the fingers in direct contact with the incoming dNTP. This experimental approach can be used to measure distances between any site on the surface of the protein and an interacting molecule.Reverse transcriptase (RT) is the enzyme responsible for copying the single-stranded RNA genome of retroviruses into double-stranded DNA (dsDNA) (6,37,39). RT has two enzymatic activities: a polymerase that can copy either an RNA or a DNA template and an RNase H that can degrade RNA if (and only if) it is a part of an RNA-DNA hybrid. The RT of human immunodeficiency virus type 1 (HIV-1) is an important target for anti-HIV drugs; a number of the drugs approved for the treatment of HIV infections are RT inhibitors (27).HIV-1 RT is a heterodimer composed of two subunits: The larger, p66, is 560 amino acids long, and the smaller, p51, contains the first 440 residues of ...

show abstract

Section: Gly Pro Glumentioning

confidence: 99%

Cross-Linking of the Fingers Subdomain of Human Immunodeficiency Virus Type 1 Reverse Transcriptase to Template-Primer

Peletskaya

Boyer²,

Kogon³

et al. 2001

J Virol

View full text Add to dashboard Cite

show abstract

“…On the basis of studies [12,13] on the oxidation of thiolsulfinates with periodate, Oae [14] supposed, however, that the oxidation of sulfides with periodate occurs by the rate-determining attack of sulfur on the central iodine atom of periodate (1 + 6 w 7, Scheme 1) and a subsequent ligand-coupling reaction of the supposed trigonal bipyramidal intermediate (7). On the other hand, Musker and coworkers [15,16] proposed the formation of a mixed anhydride intermediate of sulfinic and iodic acids (RSO-IO 3 ) for the periodate oxidation of thiols and disulfides rather than the oxygen-transfer mechanism.…”

Section: Introductionmentioning

confidence: 99%

Mechanism for the Oxidation of Sulfides and Sulfoxides with Periodates: Reactivity of the Oxidizing Species

et al. 2009

View full text Add to dashboard Cite

DFT computations have been performed at different levels of theory to identify the mechanism for the oxidation of sulfides and sulfoxides with periodates. The periodate ion (IO 4 -), periodic acid (HIO 4 ) and their hydrated derivatives all oxidize sulfides to sulfoxides in one-step oxygen-transfer reactions and the relative reactivities are HIO 4 ϾϾ H 5 IO 6 Ͼ IO 4 -Ͼ H 4 IO 6 -ϾϾ H 3 IO 6 2-. The hydration and dissociation equilibria of the periodates are shifted towards IO 4 -in neutral and moderately acidic solutions, and sulfides are oxidized mainly with IO 4 -under normal experimental conditions. The oxygen atoms of the periodates attack the sulfides perpendicularly to the plane of the C-S-C atoms and the S···O···I atoms are in a linear arrangement in the very early transition state (TS). The sulfides are the electron donors and periodates are the

show abstract

“…N- (14), 258 (12), 189 (14), 160 (100), 148 (28), 133 (22), 105 (20). (m, 8 H); 2.66 (t, J 7.35, 4 H); 3.67 (t, J 7.20, 4 H); 7.65 ± 7.75 (m, 4 H); 7.81 ± 7.88 (m, 4 H).…”

Section: Experimental Partmentioning

confidence: 99%

“…The excess of CHCl 2 OMe was evaporated, the residual acid chloride dissolved in CH 2 Cl 2 (10 ml) and added dropwise within 30 min to a soln. of 3,3'-dithiobis[propan-1-ol] (10; 1.8 g, 9.89 mmol) [12] and Et 3 N (2.5 ml) in CH 2 Cl 2 (50 ml) at r.t. The mixture was refluxed overnight under Ar and worked up by addition of H 2 O (70 ml) and extraction of the aq.…”

Section: Experimental Partmentioning

confidence: 99%

“…The synthesis of the dithio derivative 11, bearing an ester rather than an amide function as a link between the tris(oxyethanediyl) moiety and the thio group, was performed by reaction of 3,3'-dithiobis[propanol] (10; obtained from 3-bromopropanol [12]) with the acid chloride of 7. The dithio derivatives 8a, b and 11 were reduced with Zn in AcOH to the thiols 9a, b and 12 in almost quantitative yield.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Synthesis ofω-Substituted Alkanethiols and (Bromomethyl)methylthiomalonates

Pfammatter¹,

Siljegovic²,

Darbre³

et al. 2001

HCA

View full text Add to dashboard Cite

Several multifunctional derivatives of methylthiomalonic acid ( 2-(thiocarboxy)acetic acid), i.e. 20a, b, 21, 22a, b, and 24, were prepared from thiols bearing a functionalized head group, i.e. from 9a, b, 12, and 16d, f (Schemes 4 and 5). The association constants of the two dithio podands 8b and 11 with K were determined.Introduction. ± For development of models of the coenzyme-B 12 -dependent methylmalonyl-CoA mutase, we have prepared a variety of (bromomethyl)methylthiomalonates ( 2-(bromomethyl)-2-methyl-3-oxo-3-(alkylthio)propanoates) with head groups for molecular recognition. These model substrates are to be used to investigate the efficiency of the methylmalonyl-succinyl rearrangement when the substrate and the vitamin-B 12 molecule are held together by noncovalent interactions. The concept of enhancing the rearrangement by peripheral association of appropriate groups is based on the idea that enzymes or enzyme-coenzyme complexes must recognize their substrates and associate with them through noncovalent bonds to provide the orientation and proximity necessary for catalysis [1 ± 4]. Hitherto, we have reported a hydrophobic model, where lipophilic alkane chains are used for the association between the methylmalonyl moiety and the vitamin B 12 , appropriately modified in the periphery, and two models based on association in aprotic solvents between an A´T and a C´G base pair, respectively [5 ± 8]. Enhanced rearrangement has been observed for the hydrophobic and the A´T mode [5] [6]. In further persuit of vitamin-B 12 -related concepts for molecular recognition between methylmalonyl substrates and the catalyst, we considered the association between polyether (podand) units mediated by cations as well as the interaction between carbohydrate-derived units. We report here the preparation of alkanethiols bearing a polyether moiety or a pentahydroxyhexanoyl head group as well as the efficient synthesis of thioesters thereof. First results for the binding constants between two polyethers with alkali cations are reported.

show abstract

Kinetics of the aqueous periodate oxidation of aliphatic disulfides and thioethers

Cited by 22 publications

References 0 publications

Cross-Linking of the Fingers Subdomain of Human Immunodeficiency Virus Type 1 Reverse Transcriptase to Template-Primer

Cross-Linking of the Fingers Subdomain of Human Immunodeficiency Virus Type 1 Reverse Transcriptase to Template-Primer

Mechanism for the Oxidation of Sulfides and Sulfoxides with Periodates: Reactivity of the Oxidizing Species

Synthesis ofω-Substituted Alkanethiols and (Bromomethyl)methylthiomalonates

Contact Info

Product

Resources

About