Long Đinh - Academia.edu (original) (raw)

Papers by Long Đinh

Research paper thumbnail of Multi-Substituted Quinolines as HIV-1 Integrase Allosteric Inhibitors

Viruses

Allosteric HIV-1 integrase (IN) inhibitors, or ALLINIs, are a new class of antiviral agents that ... more Allosteric HIV-1 integrase (IN) inhibitors, or ALLINIs, are a new class of antiviral agents that bind at the dimer interface of the IN, away from the enzymatic catalytic site and block viral replication by triggering an aberrant multimerization of the viral enzyme. To further our understanding of the important binding features of multi-substituted quinoline-based ALLINIs, we have examined the IN multimerization and antiviral properties of substitution patterns at the 6 or 8 position. We found that the binding properties of these ALLINIs are negatively impacted by the presence of bulky substitutions at these positions. In addition, we have observed that the addition of bromine at either the 6 (6-bromo) or 8 (8-bromo) position conferred better antiviral properties. Finally, we found a significant loss of potency with the 6-bromo when tested with the ALLINI-resistant IN A128T mutant virus, while the 8-bromo analog retained full effectiveness.

Research paper thumbnail of Methods, processes and materials for dispensing and recovering supported fluorous reaction components

Research paper thumbnail of π Complexes of Fluorous Alkynes, Cyclobutadienes, and Benzenes:  Syntheses and Phase Properties of Cobalt and Chromium Tricarbonyl Adducts

Organometallics, 2006

Reactions of Cr(CO) 6 and fluorous benzenes C 6 H 6-x ((CH 2) 3 R f8) x (x) a, 1; b, 2 (1,2); c, ... more Reactions of Cr(CO) 6 and fluorous benzenes C 6 H 6-x ((CH 2) 3 R f8) x (x) a, 1; b, 2 (1,2); c, 2 (1,3); d, 2 (1,4); e, 3 (1,3,5); R f8) (CF 2) 7 CF 3 ; dibutyl ether, 140°C) give the π complexes (η 6-C 6 H 6-x ((CH 2) 3 R f8) x)-Cr(CO) 3 (1a-e; 92-42%); p-R f8 (CH 2) 3 C 6 H 4 CH(S(CH 2) 3 R f8)(CH 2) 2 R f8 affords an analogous adduct (1f; 47%). The CF 3 C 6 F 11 /toluene partition coefficients of 1a-f increase with the number of ponytails (three, 99:1 to 97:3; two, 91:9; one, 49:51); the fluorophilicities are only slightly less than a-f. The IR ν CO values show any residual inductive effect of the perfluoroalkyl groups at chromium to be slight. The reaction of LiCtCSi(CH 3) 3 and R f8 (CH 2) 3 I gives the fluorous alkyne R f8 (CH 2) 3 CtCSi(CH 3) 3 (2; 63%). Addition of wet n-Bu 4 N + Faffords R f8 (CH 2) 3 CtCH (71%), which upon treatment with t-BuLi and R f8 (CH 2) 3 I yields R f8 (CH 2) 3 CtC(CH 2) 3 R f8 (4; 58%). The reaction of 2 and Co 2 (CO) 8 gives the alkyne complex Co 2 (CO) 6 (η 2-µ-R f8 (CH 2) 3 CCSi(CH 3) 3) (88%). Reactions of 2 or 4 with (η 5-C 5 H 5)Co(CO) 2 (2:1, decane, 150-160°C) give the π cyclobutadiene complexes (η 5-C 5 H 5)Co{η 4-C 4 [Z] 2 [(CH 2) 3 R f8 ] 2 } (Z) Si(CH 3) 3 , 6, 70%; (CH 2) 3 R f8 , 7, 32%). The CF 3 C 6 F 11 /toluene partition coefficients show 6 and 7 to be more fluorophilic than their precursors 2 and 4, despite the added (η 5-C 5 H 5)Co groups.

Research paper thumbnail of Monophasic and biphasic hydrosilylations of enones and ketones using a fluorous rhodium catalyst that is easily recycled under fluorous?organic liquid?liquid biphasic conditions

New Journal of Chemistry, 2005

Additions of PhMe 2 SiH to 2-cyclohexen-1-one, 2-cyclopenten-1-one, 4, 4-dimethyl-2-cyclohexen-1-... more Additions of PhMe 2 SiH to 2-cyclohexen-1-one, 2-cyclopenten-1-one, 4, 4-dimethyl-2-cyclohexen-1-one, and cyclohexanone (11) are catalyzed by the rhodium complexes ClRh [P (CH 2 CH 2 (CF 2) n− 1 CF 3) 3] 3 (1; n= 6, 8), which have very high affinities for ...

Research paper thumbnail of Syntheses and structures of missing links among polybromocyclopentadienyl rhenium and manganese tricarbonyl complexes

Journal of Organometallic Chemistry, 2005

Reactions of diazocyclopentadiene and NBS at appropriate stoichiometries give 2,5-dibromodiazocyc... more Reactions of diazocyclopentadiene and NBS at appropriate stoichiometries give 2,5-dibromodiazocyclopentadiene and 2,3,5-tribromodiazocyclopentadiene in 40% and 30% yields, respectively, after chromatography. These react with BrRe(CO) 5 or BrMn(CO) 5 (80°C, CF 3 C 6 H 5) to give (g 5-1,2,3-C 5 H 2 Br 3)M(CO) 3 (3; M = a, Re; b, Mn) and (g 5-C 5 HBr 4)M(CO) 3 (4a,b) in 75-85% yields. In the case of 4a, the intermediate g 1-cyclopentadienyl complex (g 1-C 5 HBr 4)Re(CO) 5 (4 0 a) can be isolated (44%). An isomer of 3b, (g 5-1,2,4-C 5 H 2 Br 3)Mn(CO) 3 , is accessed by desilylating previously reported (g 5-1,2,4-C 5 (SiMe 3) 2 Br 3)Mn(CO) 3 with CsF/MeOH (85%). The reaction of tetrabromodiazocyclopentadiene and BrRe(CO) 5 at 80°C in CF 3 C 6 H 5 gives the g 1-cyclopentadienyl complex (g 1-C 5 Br 5)Re(CO) 5 (5 0 a, 74%) which cannot be induced to decarbonylate to (g 5-C 5 Br 5)Re(CO) 3 (5a) under a variety of conditions. However, 5a can be isolated (45%) when a similar reaction is conducted at 120°C. The IR properties of the preceding complexes are compared, and the crystal structures of 3a, 3b, 5a, and 5 0 a are determined and analyzed.

Research paper thumbnail of Synthesis, structure, and reactivity of fluorous phosphorus/carbon/phosphorus pincer ligands and metal complexes

Dalton Transactions, 2005

Research paper thumbnail of “Heavy Fluorous” Cyclopentadienes and Cyclopentadienyl Complexes with Three to Five Ponytails: Facile Syntheses from Polybromocyclopentadienyl Complexes, Phase Properties, and Electronic Effects

Chemistry - A European Journal, 2005

The reactions between [(eta5-C5H(5-x)Br(x))M(CO)3] (M = Re, Mn; x = 1, 3, 4, 5) and [IZn[(CH2)(n)... more The reactions between [(eta5-C5H(5-x)Br(x))M(CO)3] (M = Re, Mn; x = 1, 3, 4, 5) and [IZn[(CH2)(n)R(f8)]] (n = 2, 3; R(f8) = (CF2)7CF3) in the presence of [Cl2PdL2] catalysts give the title complexes [[eta5-C5H(5-x)[(CH2)(n)R(f8)]x]M(CO)3]. In the case of x = 5, the major product is actually [[eta5-C5H[(CH2)(n)R(f8)]4]M(CO)3], in which one of the bromides has been substituted by hydride. Minor amounts of multiple hydride substitution products are formed, all of them readily separable on fluorous silica gel. Irradiation of the manganese complexes in CF3C6H5/MeOH/ether gives uncoordinated cyclopentadienes, which can be deprotonated and reattached to other metals. Partition coefficients have been measured (CF3C6F11/toluene): complexes with three or more ponytails are highly fluorophilic, with values of > 99.8: < 0.2. The IR [symbol: see text]CO bands have been used to probe the inductive effects of the ponytails at the metal centers.

Research paper thumbnail of Convenient syntheses of “heavy fluorous” cyclopentadienes and cyclopentadienyl complexes with three to five ponytails

Chem. Commun., 2004

Reactions of (eta5-C5H(5-x)Brx)M(CO)3(M = Re, Mn; x= 1, 3, 4, 5) and IZn(CH2)2R(f8) in the presen... more Reactions of (eta5-C5H(5-x)Brx)M(CO)3(M = Re, Mn; x= 1, 3, 4, 5) and IZn(CH2)2R(f8) in the presence of Cl2PdL2 catalysts give the title complexes (eta5)-C5H(5-x)(CH2)2R(f8)x)M(CO3), accompanied in the case of x= 5 by hydride-transfer byproducts. Extremely high fluorophilicities are realized, and the cyclopentadienyl ligands are readily detached (hnu) from the manganese complexes.

Research paper thumbnail of “Katalysatoren am laufenden Band” - Teflon: eine neue Methode zur Applikation und Wiedergewinnung homogener fluoriger Katalysatoren

Angewandte Chemie, 2005

Wir danken dem Bundesministerium für Bildung und Forschung für finanzielle Unterstützung, Prof. D... more Wir danken dem Bundesministerium für Bildung und Forschung für finanzielle Unterstützung, Prof. Dr. A. Behr und Dr. R. Roll (Universität Dortmund) für Rhodium-Messungen und Prof. Dr. D. Curran (University of Pittsburgh) für wertvolle Diskussionen. Hintergrundinformationen zu diesem Beitrag sind im WWW unter http://www.angewandte.de zu finden oder können beim Autor angefordert werden.

Research paper thumbnail of “Catalyst-on-a-Tape”—Teflon: A New Delivery and Recovery Method for Homogeneous Fluorous Catalysts

Angewandte Chemie International Edition, 2005

Dinh, LV and Gladysz, JA (2005),“Catalyst-on-a-Tape”—Teflon: A New Delivery and Recovery Method f... more Dinh, LV and Gladysz, JA (2005),“Catalyst-on-a-Tape”—Teflon: A New Delivery and Recovery Method for Homogeneous Fluorous Catalysts. Angewandte Chemie International Edition, 44: 4095–4097. doi: 10.1002/anie. 200500237

Research paper thumbnail of Multi-Substituted Quinolines as HIV-1 Integrase Allosteric Inhibitors

Viruses

Allosteric HIV-1 integrase (IN) inhibitors, or ALLINIs, are a new class of antiviral agents that ... more Allosteric HIV-1 integrase (IN) inhibitors, or ALLINIs, are a new class of antiviral agents that bind at the dimer interface of the IN, away from the enzymatic catalytic site and block viral replication by triggering an aberrant multimerization of the viral enzyme. To further our understanding of the important binding features of multi-substituted quinoline-based ALLINIs, we have examined the IN multimerization and antiviral properties of substitution patterns at the 6 or 8 position. We found that the binding properties of these ALLINIs are negatively impacted by the presence of bulky substitutions at these positions. In addition, we have observed that the addition of bromine at either the 6 (6-bromo) or 8 (8-bromo) position conferred better antiviral properties. Finally, we found a significant loss of potency with the 6-bromo when tested with the ALLINI-resistant IN A128T mutant virus, while the 8-bromo analog retained full effectiveness.

Research paper thumbnail of Methods, processes and materials for dispensing and recovering supported fluorous reaction components

Research paper thumbnail of π Complexes of Fluorous Alkynes, Cyclobutadienes, and Benzenes:  Syntheses and Phase Properties of Cobalt and Chromium Tricarbonyl Adducts

Organometallics, 2006

Reactions of Cr(CO) 6 and fluorous benzenes C 6 H 6-x ((CH 2) 3 R f8) x (x) a, 1; b, 2 (1,2); c, ... more Reactions of Cr(CO) 6 and fluorous benzenes C 6 H 6-x ((CH 2) 3 R f8) x (x) a, 1; b, 2 (1,2); c, 2 (1,3); d, 2 (1,4); e, 3 (1,3,5); R f8) (CF 2) 7 CF 3 ; dibutyl ether, 140°C) give the π complexes (η 6-C 6 H 6-x ((CH 2) 3 R f8) x)-Cr(CO) 3 (1a-e; 92-42%); p-R f8 (CH 2) 3 C 6 H 4 CH(S(CH 2) 3 R f8)(CH 2) 2 R f8 affords an analogous adduct (1f; 47%). The CF 3 C 6 F 11 /toluene partition coefficients of 1a-f increase with the number of ponytails (three, 99:1 to 97:3; two, 91:9; one, 49:51); the fluorophilicities are only slightly less than a-f. The IR ν CO values show any residual inductive effect of the perfluoroalkyl groups at chromium to be slight. The reaction of LiCtCSi(CH 3) 3 and R f8 (CH 2) 3 I gives the fluorous alkyne R f8 (CH 2) 3 CtCSi(CH 3) 3 (2; 63%). Addition of wet n-Bu 4 N + Faffords R f8 (CH 2) 3 CtCH (71%), which upon treatment with t-BuLi and R f8 (CH 2) 3 I yields R f8 (CH 2) 3 CtC(CH 2) 3 R f8 (4; 58%). The reaction of 2 and Co 2 (CO) 8 gives the alkyne complex Co 2 (CO) 6 (η 2-µ-R f8 (CH 2) 3 CCSi(CH 3) 3) (88%). Reactions of 2 or 4 with (η 5-C 5 H 5)Co(CO) 2 (2:1, decane, 150-160°C) give the π cyclobutadiene complexes (η 5-C 5 H 5)Co{η 4-C 4 [Z] 2 [(CH 2) 3 R f8 ] 2 } (Z) Si(CH 3) 3 , 6, 70%; (CH 2) 3 R f8 , 7, 32%). The CF 3 C 6 F 11 /toluene partition coefficients show 6 and 7 to be more fluorophilic than their precursors 2 and 4, despite the added (η 5-C 5 H 5)Co groups.

Research paper thumbnail of Monophasic and biphasic hydrosilylations of enones and ketones using a fluorous rhodium catalyst that is easily recycled under fluorous?organic liquid?liquid biphasic conditions

New Journal of Chemistry, 2005

Additions of PhMe 2 SiH to 2-cyclohexen-1-one, 2-cyclopenten-1-one, 4, 4-dimethyl-2-cyclohexen-1-... more Additions of PhMe 2 SiH to 2-cyclohexen-1-one, 2-cyclopenten-1-one, 4, 4-dimethyl-2-cyclohexen-1-one, and cyclohexanone (11) are catalyzed by the rhodium complexes ClRh [P (CH 2 CH 2 (CF 2) n− 1 CF 3) 3] 3 (1; n= 6, 8), which have very high affinities for ...

Research paper thumbnail of Syntheses and structures of missing links among polybromocyclopentadienyl rhenium and manganese tricarbonyl complexes

Journal of Organometallic Chemistry, 2005

Reactions of diazocyclopentadiene and NBS at appropriate stoichiometries give 2,5-dibromodiazocyc... more Reactions of diazocyclopentadiene and NBS at appropriate stoichiometries give 2,5-dibromodiazocyclopentadiene and 2,3,5-tribromodiazocyclopentadiene in 40% and 30% yields, respectively, after chromatography. These react with BrRe(CO) 5 or BrMn(CO) 5 (80°C, CF 3 C 6 H 5) to give (g 5-1,2,3-C 5 H 2 Br 3)M(CO) 3 (3; M = a, Re; b, Mn) and (g 5-C 5 HBr 4)M(CO) 3 (4a,b) in 75-85% yields. In the case of 4a, the intermediate g 1-cyclopentadienyl complex (g 1-C 5 HBr 4)Re(CO) 5 (4 0 a) can be isolated (44%). An isomer of 3b, (g 5-1,2,4-C 5 H 2 Br 3)Mn(CO) 3 , is accessed by desilylating previously reported (g 5-1,2,4-C 5 (SiMe 3) 2 Br 3)Mn(CO) 3 with CsF/MeOH (85%). The reaction of tetrabromodiazocyclopentadiene and BrRe(CO) 5 at 80°C in CF 3 C 6 H 5 gives the g 1-cyclopentadienyl complex (g 1-C 5 Br 5)Re(CO) 5 (5 0 a, 74%) which cannot be induced to decarbonylate to (g 5-C 5 Br 5)Re(CO) 3 (5a) under a variety of conditions. However, 5a can be isolated (45%) when a similar reaction is conducted at 120°C. The IR properties of the preceding complexes are compared, and the crystal structures of 3a, 3b, 5a, and 5 0 a are determined and analyzed.

Research paper thumbnail of Synthesis, structure, and reactivity of fluorous phosphorus/carbon/phosphorus pincer ligands and metal complexes

Dalton Transactions, 2005

Research paper thumbnail of “Heavy Fluorous” Cyclopentadienes and Cyclopentadienyl Complexes with Three to Five Ponytails: Facile Syntheses from Polybromocyclopentadienyl Complexes, Phase Properties, and Electronic Effects

Chemistry - A European Journal, 2005

The reactions between [(eta5-C5H(5-x)Br(x))M(CO)3] (M = Re, Mn; x = 1, 3, 4, 5) and [IZn[(CH2)(n)... more The reactions between [(eta5-C5H(5-x)Br(x))M(CO)3] (M = Re, Mn; x = 1, 3, 4, 5) and [IZn[(CH2)(n)R(f8)]] (n = 2, 3; R(f8) = (CF2)7CF3) in the presence of [Cl2PdL2] catalysts give the title complexes [[eta5-C5H(5-x)[(CH2)(n)R(f8)]x]M(CO)3]. In the case of x = 5, the major product is actually [[eta5-C5H[(CH2)(n)R(f8)]4]M(CO)3], in which one of the bromides has been substituted by hydride. Minor amounts of multiple hydride substitution products are formed, all of them readily separable on fluorous silica gel. Irradiation of the manganese complexes in CF3C6H5/MeOH/ether gives uncoordinated cyclopentadienes, which can be deprotonated and reattached to other metals. Partition coefficients have been measured (CF3C6F11/toluene): complexes with three or more ponytails are highly fluorophilic, with values of > 99.8: < 0.2. The IR [symbol: see text]CO bands have been used to probe the inductive effects of the ponytails at the metal centers.

Research paper thumbnail of Convenient syntheses of “heavy fluorous” cyclopentadienes and cyclopentadienyl complexes with three to five ponytails

Chem. Commun., 2004

Reactions of (eta5-C5H(5-x)Brx)M(CO)3(M = Re, Mn; x= 1, 3, 4, 5) and IZn(CH2)2R(f8) in the presen... more Reactions of (eta5-C5H(5-x)Brx)M(CO)3(M = Re, Mn; x= 1, 3, 4, 5) and IZn(CH2)2R(f8) in the presence of Cl2PdL2 catalysts give the title complexes (eta5)-C5H(5-x)(CH2)2R(f8)x)M(CO3), accompanied in the case of x= 5 by hydride-transfer byproducts. Extremely high fluorophilicities are realized, and the cyclopentadienyl ligands are readily detached (hnu) from the manganese complexes.

Research paper thumbnail of “Katalysatoren am laufenden Band” - Teflon: eine neue Methode zur Applikation und Wiedergewinnung homogener fluoriger Katalysatoren

Angewandte Chemie, 2005

Wir danken dem Bundesministerium für Bildung und Forschung für finanzielle Unterstützung, Prof. D... more Wir danken dem Bundesministerium für Bildung und Forschung für finanzielle Unterstützung, Prof. Dr. A. Behr und Dr. R. Roll (Universität Dortmund) für Rhodium-Messungen und Prof. Dr. D. Curran (University of Pittsburgh) für wertvolle Diskussionen. Hintergrundinformationen zu diesem Beitrag sind im WWW unter http://www.angewandte.de zu finden oder können beim Autor angefordert werden.

Research paper thumbnail of “Catalyst-on-a-Tape”—Teflon: A New Delivery and Recovery Method for Homogeneous Fluorous Catalysts

Angewandte Chemie International Edition, 2005

Dinh, LV and Gladysz, JA (2005),“Catalyst-on-a-Tape”—Teflon: A New Delivery and Recovery Method f... more Dinh, LV and Gladysz, JA (2005),“Catalyst-on-a-Tape”—Teflon: A New Delivery and Recovery Method for Homogeneous Fluorous Catalysts. Angewandte Chemie International Edition, 44: 4095–4097. doi: 10.1002/anie. 200500237