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O'Bryant SE, Zhang F, Petersen M, Hall J, Johnson LA, Yaffe K, Braskie M, Rissman RA, Vig R, Toga AW. Neurodegeneration from the AT(N) framework is different among Mexican Americans compared to non-Hispanic Whites: A Health & Aging Brain among Latino Elders (HABLE) Study. Alzheimers Dement (Amst) 2022; 14:e12267. [PMID: 35155729 PMCID: PMC8828994 DOI: 10.1002/dad2.12267] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 07/29/2021] [Accepted: 10/18/2021] [Indexed: 01/18/2023]
Abstract
INTRODUCTION We sought to examine a magnetic resonance imaging (MRI)-based marker of neurodegeneration from the AT(N) (amyloid/tau/neurodegeneration) framework among a multi-ethnic, community-dwelling cohort. METHODS Community-dwelling Mexican Americans and non-Hispanic White adults and elders were recruited. All participants underwent comprehensive assessments including an interview, functional exam, clinical labs, informant interview, neuropsychological testing and 3T MRI of the brain. A neurodegeneration MRI meta-region of interest (ROI) biomarker for the AT(N) framework was calculated. RESULTS Data were examined from n = 1305 participants. Mexican Americans experienced N at significantly younger ages. The N biomarker was significantly associated with cognitive outcomes. N was significantly impacted by cardiovascular factors (e.g., total cholesterol, low-density lipoprotein) among non-Hispanic Whites whereas diabetes (glucose, HbA1c, duration of diabetes) and sociocultural (household income, acculturation) factors were strongly associated with N among Mexican Americans. DISCUSSION The prevalence, progression, timing, and sequence of the AT(N) biomarkers must be examined across diverse populations.
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Affiliation(s)
- Sid E. O'Bryant
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Fan Zhang
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Family MedicineUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Melissa Petersen
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Family MedicineUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - James Hall
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Pharmacology and NeuroscienceUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Leigh A. Johnson
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Pharmacology and NeuroscienceUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Kristine Yaffe
- Department of Psychiatry, Neurology, and Epidemiology and BiostatisticsUniversity of California, San FranciscoSan FranciscoCaliforniaUSA
- San Francisco VA Medical CenterSan FranciscoCaliforniaUSA
| | - Meredith Braskie
- Imaging Genetics CenterUSC Stevens Neuroimaging and Informatics InstituteKeck School of Medicine of USCUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Robert A. Rissman
- Department of NeurosciencesUniversity of California, San DiegoSan DiegoCaliforniaUSA
- Veterans Affairs San Diego Healthcare SystemSan DiegoCaliforniaUSA
| | - Rocky Vig
- ImagingMidtown Medical ImagingFort WorthTexasUSA
| | - Arthur W. Toga
- Laboratory of Neuro ImagingUSC Stevens Neuroimaging and Informatics InstituteKeck School of Medicine of USCUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - for the HABLE Study Team
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
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O’Bryant SE, Zhang F, Petersen M, Hall JR, Johnson LA, Yaffe K, Braskie M, Vig R, Toga AW, Rissman RA. Proteomic Profiles of Neurodegeneration Among Mexican Americans and Non-Hispanic Whites in the HABS-HD Study. J Alzheimers Dis 2022; 86:1243-1254. [PMID: 35180110 PMCID: PMC9376967 DOI: 10.3233/jad-210543] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Hispanics are expected to experience the largest increase in Alzheimer's disease (AD) and AD related dementias over the next several decades. However, few studies have examined biomarkers of AD among Mexican Americans, the largest segment of the U.S. Hispanic population. OBJECTIVE We sought to examine proteomic profiles of an MRI-based marker of neurodegeneration from the AT(N) framework among a multi-ethnic, community-dwelling cohort. METHODS Community-dwelling Mexican Americans and non-Hispanic white adults and elders were recruited. All participants underwent comprehensive assessments including an interview, functional exam, clinical labs, informant interview, neuropsychological testing, and 3T MRI of the brain. A neurodegeneration MRI meta-ROI biomarker for the AT(N) framework was calculated. RESULTS Data was examined from n = 1,291 participants. Proteomic profiles were highly accurate for detecting neurodegeneration (i.e., N+) among both Mexican Americans (AUC = 1.0) and non-Hispanic whites (AUC = 0.98). The proteomic profile of N + was different between ethnic groups. Further analyses revealed that the proteomic profiles of N + varied by diagnostic status (control, MCI, dementia) and ethnicity (Mexican American versus non-Hispanic whites) though diagnostic accuracy was high for all classifications. CONCLUSION A proteomic profile of neurodegeneration has tremendous value and point towards novel diagnostic and intervention opportunities. The current findings demonstrate that the underlying biological factors associated with neurodegeneration are different between Mexican Americans versus non-Hispanic whites as well as at different levels of disease progression.
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Affiliation(s)
- Sid E. O’Bryant
- Institute for Translational Research, University of North Texas Health Science Center, Fort Worth, Texas, USA,Address correspondence to: Sid O’Bryant, Ph.D., University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, Texas, 76107 USA; ; 1+817-735-2962
| | - Fan Zhang
- Institute for Translational Research, University of North Texas Health Science Center, Fort Worth, Texas, USA,Department of Family Medicine, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Melissa Petersen
- Institute for Translational Research, University of North Texas Health Science Center, Fort Worth, Texas, USA,Department of Family Medicine, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - James R. Hall
- Institute for Translational Research, University of North Texas Health Science Center, Fort Worth, Texas, USA,Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Leigh A. Johnson
- Institute for Translational Research, University of North Texas Health Science Center, Fort Worth, Texas, USA,Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Kristine Yaffe
- Department of Psychiatry, Neurology, and Epidemiology and Biostatistics, University of California, San Francisco, CA, USA,San Francisco VA Medical Center, San Francisco, CA, USA
| | - Meredith Braskie
- Imaging Genetics Center, USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Rocky Vig
- Imaging, Midtown Medical Imaging, Fort Worth, Texas, USA; Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Arthur W. Toga
- Laboratory of Neuro Imaging, USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Robert A. Rissman
- Department of Neurosciences, University of California, San Diego, La Jolla, CA and Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
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O'Bryant SE, Johnson LA, Barber RC, Braskie MN, Christian B, Hall JR, Hazra N, King K, Kothapalli D, Large S, Mason D, Matsiyevskiy E, McColl R, Nandy R, Palmer R, Petersen M, Philips N, Rissman RA, Shi Y, Toga AW, Vintimilla R, Vig R, Zhang F, Yaffe K. The Health & Aging Brain among Latino Elders (HABLE) study methods and participant characteristics. Alzheimers Dement (Amst) 2021; 13:e12202. [PMID: 34189247 PMCID: PMC8215806 DOI: 10.1002/dad2.12202] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 03/25/2021] [Accepted: 04/11/2021] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Mexican Americans remain severely underrepresented in Alzheimer's disease (AD) research. The Health & Aging Brain among Latino Elders (HABLE) study was created to fill important gaps in the existing literature. METHODS Community-dwelling Mexican Americans and non-Hispanic White adults and elders (age 50 and above) were recruited. All participants underwent comprehensive assessments including an interview, functional exam, clinical labs, informant interview, neuropsychological testing, and 3T magnetic resonance imaging (MRI) of the brain. Amyloid and tau positron emission tomography (PET) scans were added at visit 2. Blood samples were stored in the Biorepository. RESULTS Data was examined from n = 1705 participants. Significant group differences were found in medical, demographic, and sociocultural factors. Cerebral amyloid and neurodegeneration imaging markers were significantly different between Mexican Americans and non-Hispanic Whites. DISCUSSION The current data provide strong support for continued investigations that examine the risk factors for and biomarkers of AD among diverse populations.
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Affiliation(s)
- Sid E. O'Bryant
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Pharmacology and NeuroscienceUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Leigh A. Johnson
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Pharmacology and NeuroscienceUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Robert C. Barber
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Pharmacology and NeuroscienceUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Meredith N. Braskie
- Imaging Genetics Center, Stevens Neuroimaging and Informatics InstituteKeck School of Medicine, USCLos AngelesCaliforniaUSA
| | - Bradley Christian
- Waisman Center, Departments of Physics and PsychiatryUniversity of Wisconsin MadisonMadisonWisconsinUSA
| | - James R. Hall
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Pharmacology and NeuroscienceUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Nalini Hazra
- Imaging Genetics Center, Stevens Neuroimaging and Informatics InstituteKeck School of Medicine, USCLos AngelesCaliforniaUSA
| | - Kevin King
- Department of NeuroradiologyBarrow Neurological InstitutePhoenixArizonaUSA
| | - Deydeep Kothapalli
- Imaging Genetics Center, Stevens Neuroimaging and Informatics InstituteKeck School of Medicine, USCLos AngelesCaliforniaUSA
| | - Stephanie Large
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Pharmacology and NeuroscienceUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - David Mason
- Department of Family MedicineUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Elizabeth Matsiyevskiy
- Imaging Genetics Center, Stevens Neuroimaging and Informatics InstituteKeck School of Medicine, USCLos AngelesCaliforniaUSA
| | - Roderick McColl
- Department of RadiologyUT Southwestern Medical CenterDallasTexasUSA
| | - Rajesh Nandy
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Biostatistics & EpidemiologyUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Raymond Palmer
- Department of Family Practice and Community Medicine, Joe R & Teresa Lozano Long School of MedicineThe University of Texas Health Science Center at San AntonioSan AntonioTexasUSA
| | - Melissa Petersen
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Family MedicineUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Nicole Philips
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Pharmacology and NeuroscienceUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Robert A. Rissman
- Department of NeurosciencesUniversity of CaliforniaSan Diego, La JollaCaliforniaUSA
- Veterans Affairs San Diego Healthcare SystemSan DiegoCaliforniaUSA
| | - Yonggang Shi
- Laboratory of Neuro Imaging, USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USCUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Arthur W. Toga
- Laboratory of Neuro Imaging, USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USCUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Raul Vintimilla
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Pharmacology and NeuroscienceUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Rocky Vig
- Imaging, Midtown Medical ImagingFort WorthTexasUSA
| | - Fan Zhang
- Institute for Translational ResearchUniversity of North Texas Health Science CenterFort WorthTexasUSA
- Department of Family MedicineUniversity of North Texas Health Science CenterFort WorthTexasUSA
| | - Kristine Yaffe
- Department of Psychiatry, Neurology, and Epidemiology and BiostatisticsUniversity of CaliforniaSan FranciscoCaliforniaUSA
- San Francisco VA Medical CenterSan FranciscoCaliforniaUSA
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Kiss S, Vig R, Nagy Z, Geher P, Szentesi M. THU0147 Comparison of biological hasards of 166-holmium-phytate and 90-yttrium used for radiosynoviorthesis. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2012-eular.2112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Vig R, Kilic Ü, Kilic E, Gassmann M, Hermann DM. Delayed erythropoietin administration promotes neuronal survival and axonal sprouting with an increase in the motor recovery after mild focal cerebral ischaemia in mice. Akt Neurol 2009. [DOI: 10.1055/s-0029-1238793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Kilic E, Spudich A, Kilic Ü, Rentsch KM, Vig R, Matter CM, Wunderli-Allenspach H, Fritschy JM, Bassetti CL, Hermann DM. ABCC1: a gateway for drugs to the ischaemic brain. Akt Neurol 2009. [DOI: 10.1055/s-0029-1238448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Sudbeck EA, Mao C, Vig R, Venkatachalam TK, Tuel-Ahlgren L, Uckun FM. Structure-based design of novel dihydroalkoxybenzyloxopyrimidine derivatives as potent nonnucleoside inhibitors of the human immunodeficiency virus reverse transcriptase. Antimicrob Agents Chemother 1998; 42:3225-33. [PMID: 9835518 PMCID: PMC106026 DOI: 10.1128/aac.42.12.3225] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Two highly potent dihydroalkoxybenzyloxopyrimidine (DABO) derivatives targeting the nonnucleoside inhibitor (NNI) binding site of human immunodeficiency virus (HIV) reverse transcriptase (RT) have been designed based on the structure of the NNI binding pocket and tested for anti-HIV activity. Our lead DABO derivative, 5-isopropyl-2-[(methylthiomethyl)thio]-6-(benzyl)-pyrimidin-4-(1H)-on e, elicited potent inhibitory activity against purified recombinant HIV RT and abrogated HIV replication in peripheral blood mononuclear cells at nanomolar concentrations (50% inhibitory concentration, <1 nM) but showed no detectable cytotoxicity at concentrations as high as 100 microM.
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Affiliation(s)
- E A Sudbeck
- Drug Discovery Program, Hughes Institute, St. Paul, Minnesota 55113, USA
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Venkatachalam TK, Tai HL, Vig R, Chen CL, Jan ST, Uckun FM. Enhancing effects of a mono-bromo substitution at the para position of the phenyl moiety on the metabolism and anti-HIV activity of d4T-phenyl methoxyalaninyl phosphate derivatives. Bioorg Med Chem Lett 1998; 8:3121-6. [PMID: 9873688 DOI: 10.1016/s0960-894x(98)00547-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
d4T-5'-[p-Bromophenyl methoxyalaninyl phosphate] (d4T-pBPMAP), a novel phenyl phosphate derivative of 2',3'-didehydro-2',3'-dideoxythymidine (d4T) that has an enhanced ability to undergo hydrolysis due to the electron withdrawing properties of its single bromo substituent at the para-position of the phenyl moiety, was found to yield substantially more of the key metabolite alaninyl d4T monophosphate (A-d4T-MP) than the unsubstituted d4T-5'-phenyl methoxyalaninyl phosphate or para-methoxy substituted d4T-5'-phenyl methoxyalaninyl phosphate. d4T-pBPMAP was tested for its anti-HIV-1 activity in peripheral blood mononuclear cells (PBMNC) and thymidine kinase (TK)-deficient CEM T-cells. d4T-pBPMAP was 12.6-fold more potent than the parent compound d4T in inhibiting p24 production (IC50 values: 44 nM vs 556 nM) and 41.3-fold more potent than d4T in inhibiting the reverse transcriptase (RT) activity (IC50 values: 57 nM vs 2355 nM) in HIV-1-infected TK-deficient CEM cells. Similarly, d4T-pBPMAP was more potent than the unsubstituted or para-methoxy substituted phenyl methoxyalaninyl phosphate derivatives of d4T. d4T-pBPMAP did not exhibit any detectable cytotoxicity to PBMNC or CEM cells at concentrations as high as 10,000 nM. Notably, d4T-pBPMAP was capable of inhibiting the replication of a zidovudine (ZDV/AZT)-resistant HIV-1 strain as well as HIV-2 in PBMNC at nanomolar concentrations. To our knowledge, this is the first demonstration that the potency of the d4T-aryl-phosphate derivatives can be substantially enhanced by introducing a single para-bromo substituent in the aryl moiety.
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Vig R, Mao C, Venkatachalam TK, Tuel-Ahlgren L, Sudbeck EA, Uckun FM. Rational design and synthesis of phenethyl-5-bromopyridyl thiourea derivatives as potent non-nucleoside inhibitors of HIV reserve transcriptase. Bioorg Med Chem 1998; 6:1789-97. [PMID: 9839009 DOI: 10.1016/s0968-0896(98)00108-4] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of novel phenethylthiazolylthiourea (PETT) derivatives targeting the nonnucleoside inhibitor (NNI) binding site of HIV reverse transcriptase (RT) have been designed based on the structure of the NNI binding pocket. The structure-based design and synthesis of these new PETT derivatives were complemented by biological assays of their anti-HIV activity. Modeling studies for rational drug design included the construction of a composite NNI binding pocket from nine RT-NNI crystal structures, the analyses of surface complementarity between NNI and RT, and application of Ki calculations combined with a docking procedure involving the novel PETT derivatives. The use of the composite NNI binding pocket allowed the identification and structure-based design of three promising PETT derivatives with ortho-F (2), ortho-Cl (3), and meta-F (5) substituents on the phenyl ring. These novel PETT derivatives were more active than AZT or trovirdine and showed potent anti-HIV activity with IC50[p24] values of < 1 nM and selectivity indices of > 100,000.
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Affiliation(s)
- R Vig
- Drug Discovery Program, Hughes Institute, St. Paul, MN 55113, USA
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Vig R, Venkatachalam TK, Jan ST, Uckun FM. Aryl phosphate derivatives of 3'-deoxythymidine are not potent anti-human immunodeficiency virus agents. Antivir Chem Chemother 1998; 9:439-43. [PMID: 9875397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Aryl phosphate derivatives of 3'-deoxythymidine (3dT), albeit more active than 3dT in thymidine kinase (TK)-deficient cells, are not potent anti-human immunodeficiency virus (HIV) agents and are capable of inhibiting HIV replication only at micromolar concentrations.
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Affiliation(s)
- R Vig
- Drug Discovery Program, Hughes Institute, St Paul, Minnesota 55113, USA
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Vig R, Venkatachalam TK, Uckun FM. D4T-5'-[p-bromophenyl methoxyalaninyl phosphate] as a potent and non-toxic anti-human immunodeficiency virus agent. Antivir Chem Chemother 1998; 9:445-8. [PMID: 9875398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Three aryl phosphate derivatives of 2',3'-didehydro-2',3'-dideoxythymidine (d4T) were tested for their anti-human immunodeficiency virus (HIV) activity in peripheral blood mononuclear cells (PBMC) and thymidine kinase (TK)-deficient CEM T cells. Compared to the parent compound d4T, the lead compound d4T-5'-[p-bromophenyl methoxyalaninylphosphate] with a para-bromo substituent in the aryl moiety was 12.6-fold more potent in inhibiting p24 production (IC50 values: 44 nM versus 556 nM) and 41.3-fold more potent in inhibiting the reverse transcriptase (RT) activity (IC50 values: 57 nM versus 2355 nM) in HIV-infected TK-deficient CEM cells. None of the compounds exhibited any detectable cytotoxicity to PBMC or CEM cells at concentrations as high as 10,000 nM. To our knowledge, this is the first demonstration that the potency as well as selectivity index of the d4T aryl phosphate derivatives in TK-deficient cells can be substantially enhanced by introducing a single para-bromo substituent in the phenyl moiety.
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Affiliation(s)
- R Vig
- Drug Discovery Program, Hughes Institute, St Paul, Minnesota 55113, USA
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Mao C, Vig R, Venkatachalam TK, Sudbeck EA, Uckun FM. Structure-based design of N-[2-(1-piperidinylethyl)]-N'-[2-(5-bromopyridyl)]-thiourea and N-[2-(1-piperazinylethyl)]-N'-[2-(5-bromopyridyl)]-thiourea as potent non-nucleoside inhibitors of HIV-1 reverse transcriptase. Bioorg Med Chem Lett 1998; 8:2213-8. [PMID: 9873515 DOI: 10.1016/s0960-894x(98)00384-9] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A novel computer model of the HIV reverse transcriptase (RT) non-nucleoside inhibitor (NNI) binding pocket, which was generated using high resolution crystal structure information from 9 individual RT/NNI complexes, revealed previously unrecognized ligand derivatization sites for phenethylthiazolylthiourea (PETT) derivatives. Spatial gaps surrounding the pyridyl ring of the active PETT derivative trovirdine were discovered during modeling procedures. Docking studies using the computer-generated model of the binding pocket (composite binding pocket) suggested that the replacement of the planar pyridyl ring of trovirdine with a nonplanar piperidinyl or piperazinyl ring, which occupy larger volumes, would better fill the spacious Wing 2 region of the butterfly-shaped NNI binding pocket. The anti-HIV activity of the synthesized heterocyclic compounds N-[2-(1-piperidinylethyl)]-N'-[2-(5-bromopyridyl)]-thiourea and N-[2-(1-piperazinylethyl)]-N'-[2-(5-bromopyridyl)]-thiourea was examined in HTLVIIIB-infected peripheral blood mononuclear cells. Both compounds were more potent than trovirdine and abrogated HIV replication at nanomolar concentrations without any evidence of cytotoxicity.
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Affiliation(s)
- C Mao
- Drug Discovery Program, Wayne Hughes Institute, St. Paul, MN 55113, USA
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Vig R, Mao C, Venkatachalam TK, Tuel-Ahlgren L, Sudbeck EA, Uckun FM. 5-Alkyl-2-[(methylthiomethyl)thio]-6-(benzyl)-pyrimidin-4-(1H)-ones as potent non-nucleoside reverse transcriptase inhibitors of S-DABO series. Bioorg Med Chem Lett 1998; 8:1461-6. [PMID: 9873370 DOI: 10.1016/s0960-894x(98)00250-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Novel dihydroalkoxybenzyloxopyrimidine (S-DABO) derivatives targeting the non-nucleoside inhibitor (NNI) binding site of human immunodeficiency virus (HIV) reverse transcriptase (RT) have been synthesized using a novel computer model for the NNI binding pocket and tested for their RT inhibitory activity in cell-free assays using purified recombinant HIV RT as well as for their anti-HIV activity in HTL VIIIB-infected peripheral blood mononuclear cells. Our computational approach allowed the identification of several ligand derivatization sites for the generation of more potent S-DABO derivatives. Our lead S-DABO derivative, 5-isopropyl-2-[(methylthiomethyl)thio]-6-(benzyl)-pyrimidin-4-(1H)-one (compound 3), elicited potent anti-HIV activity with an IC50 value of less than 1nM for inhibition of HIV replication without any evidence of cytotoxicity and an unprecedented selectivity index of > 100,000.
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Affiliation(s)
- R Vig
- Department of Chemistry, Wayne Hughes Institute, St. Paul, MN 55113, USA
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Chandrasekaran EV, Jain RK, Vig R, Matta KL. The enzymatic sulfation of glycoprotein carbohydrate units: blood group T-hapten specific and two other distinct Gal:3-O-sulfotransferases as evident from specificities and kinetics and the influence of sulfate and fucose residues occurring in the carbohydrate chain on C-3 sulfation of terminal Gal. Glycobiology 1997; 7:753-68. [PMID: 9376678 DOI: 10.1093/glycob/7.6.753] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Enzymatic 3-O-sulfation of terminal beta-Gal residues was investigated by screening sulfotransferase activity present in 37 human tissue specimens toward the following synthesized acceptor moieties: Galbeta1,3GalNAc alpha-O-Al, Galbeta1,4GlcNAcbeta-O-Al, Galbeta1,3GlcNAcbeta-O-Al, and mucin-type Galbeta1,4GlcNAcbeta1,6(Galbeta1,3)GalNAc alpha-O-Bn structures containing a C-3 methyl substituent on either Gal. Two distinct types of Gal: 3-O-sulfotransferases were revealed. One (Group A) was specific for the Galbeta1, 3GalNAc alpha- linkage and the other (Group B) was directed toward the Galbeta1,4GlcNAc branch beta1,6 linked to the blood group T hapten. Enzyme activities found in breast tissues were unique in showing a strict specificity for the T-hapten. Galbeta-O-allyl or benzyl did not serve as acceptors for Group A but were very active with Group B. An examination of activity present in six human sera revealed a specificity of the serum enzyme toward beta1,3 linked Gal, particularly, the T-hapten without beta1,6 branching. Group A was highly active toward T-hapten/acrylamide copolymer, anti-freeze glycoprotein, and fetuin O-glycosidic asialo glycopeptide; less active toward fetuin triantennary asialo glycopeptide; and least active toward bovine IgG diantennary glycopeptide. Group B was moderately and highly active, respectively, with the latter two glycopeptides noted and least active with the first two. Competition experiments performed with Galbeta1,3GalNAc alpha-O-Al and Galbeta1,4GlcNAcbeta1,6(Galbeta1,3)GalNAc alpha-O-Bn having a C-3 substituent (methyl or sulfate) on either Gal reinforced earlier findings on the specificity characteristics of Group A and Group B. Group A displayed a wider range of optimal activity (pH 6.0-7.4), whereas Group B possessed a peak of activity at pH 7.2. Mg2+ stimulated Group A 55% and Group B 150%, whereas Mn+2 stimulated Group B 130% but inhibited Group A 75%. Ca2+ stimulated Group B 100% but inhibited Group A 35%. Group A and Group B enzymes appeared to be of the same molecular size (<100,000 Da) as observed by Sephacryl S-100 HR column chromatography. The following effects upon Gal: 3-O-sulfotransferase activities by fucose, sulfate, and other substituents on the carbohydrate chains were noted. (1) A methyl or GlcNAc substituent on C-6 of GalNAc diminished the ability of Galbeta1,3GalNAc alpha-O-Al to act as an acceptor for Group A. (2) An alpha1,3-fucosyl residue on the beta1,6 branch in the mucin core structure did not affect the activity of Group A toward Gal linked beta1,3 to GalNAc alpha-. (3) Lewis x and Lewis a terminals did not serve as acceptors for either Group A or B enzymes. (4) Elimination of Group B activity on Gal in the beta1,6 branch owing to the presence of a 3-fucosyl or 6-sulfo group on GlcNAc did not hinder any action toward Gal linked beta1,3 to GalNAc alpha. (5) Group A activity on Gal linked beta1,3 to GalNAc remained unaffected by 3'-sulfation of the beta1,6 branch. The reverse was true for Group B. (6) The acceptor activity of the T-hapten was increased somewhat upon C-6 sulfation of GalNAc, whereas, C-6 sialylation resulted in an 85% loss of activity. (7) A novel finding was that Galbeta1,4GlcNAcbeta-O-Al and Galbeta1,3GlcNAcbeta-O-Al, upon C-6 sulfation of the GlcNAc moiety, became 100% inactive and 5- to 7-fold active, respectively, in their ability to serve as acceptors for Group B.
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Affiliation(s)
- E V Chandrasekaran
- Department of Gynecologic Oncology, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
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Koenig A, Jain R, Vig R, Norgard-Sumnicht KE, Matta KL, Varki A. Selectin inhibition: synthesis and evaluation of novel sialylated, sulfated and fucosylated oligosaccharides, including the major capping group of GlyCAM-1. Glycobiology 1997; 7:79-93. [PMID: 9061367 DOI: 10.1093/glycob/7.1.79] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Selectins interact with glycoconjugate ligands in important normal and pathological situations. While high affinity recognition of natural ligands is associated with alpha 1-3(4)fucosylated, alpha 2-3sialylated (and/or sulfated) lactosamine sequences, small oligosaccharides that potently inhibit the selectins have not been found. One possibility suggested by other investigators is that high affinity may require unusual sequences not yet tested, for example, the "major capping group" (6'-sulfo-sialyl Le(x)) of the L-selectin ligand GlyCAM-1. To explore this possibility, we synthesized a spectrum of novel synthetic and semisynthetic oligosaccharides related to those on natural ligands. In studying these molecules, we noted that binding of recombinant soluble selectins to immobilized sialyl Le(a) or 3'-sulfo-Le(x) is markedly inhibited by concentrations of chloride above the physiological range. This indicates the ionic nature of the interactions, and shows that buffers typically used in screening assays for inhibitors are not optimal. Using parameters that more closely approximate physiological conditions, we confirmed that alpha 2-3-linked sialic acids, and alpha 1-3(4)fucosylation are important for recognition. Similar results obtained with both types of immobilized targets for the three selectins indicated that the binding sites for sialic acid and sulfate are very close, or identical. While O-sulfate esters mostly improved L- and P-selectin recognition, effects depended upon their position and number. Furthermore, sulfation can also impart some "negative" specificity: the major capping group does not interact with E-selectin. The branched Core 2 sequence seemed to enhance L- and P-selectin binding, however, the best inhibitors still appeared to be sialyl Le(a) and 3'-sulfo-Le(x), with the aglycone group of the latter affecting binding. Of particular note, the "major capping group" of GlyCAM-1 was not an unusually potent nor highly selective inhibitor of L-selectin, even when studying the interaction of L-selectin with native GlyCAM-1 itself.
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Affiliation(s)
- A Koenig
- Glycobiology Program, UCSD Cancer Center, La Jolla, USA
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Hong CI, Nechaev A, Kirisits AJ, Vig R, West CR, Manouilov KK, Chu CK. Nucleoside conjugates. 15. Synthesis and biological activity of anti-HIV nucleoside conjugates of ether and thioether phospholipids. J Med Chem 1996; 39:1771-7. [PMID: 8627600 DOI: 10.1021/jm950620o] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A series of the anti-HIV nucleoside conjugates of either (1-O-alkyl) and thioether (1-S-alkyl) lipids linked by a pyrophosphate diester bond has been synthesized as micelle-forming prodrugs of the nucleosides to improve their therapeutic efficiency. These include AZT 5'-diphosphate-rac-1-S-octadecyl-2-O-palmitoyl-1-thioglycerol (1), 3'-azido-2',3'-dideoxyuridine 5'-diphosphate-rac-1-S-octadecyl-2-O-palmitoyl-1-thioglycerol (2) 2',3'-dideoxycytidine 5'-diphosphate-rac-1-S-octadecyl-2-O-palmitoyl-1-thioglycerol (3), and AZT 5'-diphosphate-rac-1-O-tetradecyl-2-O-palmitoylglycerol (4). The conjugates form micelles by sonication (mean diameters ranging 6.8-55.5 nm). Conjugate 1 protected 80% of HIV-infected CEM cells as low as 0.58 microM and lost the protection at 180 microM due to prevailing cytotoxicity, while the conjugate started to show the cytotoxicity at 100 microM. Pharmacokinetics studies showed a significant increase of half-life values (t1/2) of AZT and AZddU2 (respective t1/2 = 5.69 and 6.5 h) after administration of conjugates 1 and 2, while those after administration of AZT and AZddU were 0.28 and 0.89 h, respectively. The fractions of the prodrugs 1 and 2 converted to the parent compounds AZT and AZddU were 36% and 55%, respectively. The results indicate that AZT and AZddU thioether lipid conjugates 1 and 2 warrant further investigation.
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Affiliation(s)
- C I Hong
- Department of Neurosurgery, Roswell Park Cancer Institute, Buffalo, New York 14263, USA
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18
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Hong CI, Nechaev A, Kirisits AJ, Vig R, Hui SW, West CR. Nucleoside conjugates. 14. Synthesis and antitumor activity of 1-beta-D-arabinofuranosylcytosine conjugates of ether lipids with improved water solubility. J Med Chem 1995; 38:1629-34. [PMID: 7752187 DOI: 10.1021/jm00010a006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A series of ara-CDP-rac-1-O-alkyl-2-O-acylglycerols (9a-f), analogues of highly active ara-CDP-rac-1-O-hexadecyl-2-O-palmitoylglycerol (1) and Cytoros2 (2), was prepared, and solubility, lipophilicity, and structure-activity relationships of these conjugates were investigated. Conjugates 9a-f containing sn-1 alkyl (< C16) and sn-2 fatty acyl (< C14) and sn-1 alkyl (< C14) and sn-2 fatty acyl (< C16) substituents of the glycerol were water-soluble by shaking, while those with the sn-1 alkyl (> C16) and the sn-2 fatty acyl (> C16) such as conjugate 1 were sparingly soluble. Conjugates 9a-c,e were almost completely solubilized in water by shaking. However, a large portion of conjugates 9d and 9f in water by shaking exist in micelles with mean diameters ranging 7.0-55.2 nm. The partition coefficients (1-octanol/PBS) of the water-soluble conjugates were about 9-18 times greater than that of ara-C. A single dose (300 mg/kg) of conjugates 9d and 9f produced a significant increase in life span (ILS 206 to > 543%) with 17-67% long-term survivors (> 45 days) in mice bearing ip-implanted L1210 lymphoid leukemia. These results were comparable to those of the previous conjugate 1 and Cytoros (2). In contrast, conjugates 9a-c,e at single doses were less effective (ILS 69-178% with no long-term survivors). However, two (qd, 1, 7) or three (qd 1, 5, 9) divided doses of these conjugates were found to be as effective as a single dose of the previous conjugates. The three divided doses (150 mg/kg per day) of conjugates 9d, 9e, and 9f produced a remarkable antitumor activity in L1210 leukemic mice (ILS > 350% with > 50% long-term survivors). Because of the convenient formulation and the significant antitumor activities, the water-soluble conjugates 9d, 9e, and 9f warrant further investigation.
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Affiliation(s)
- C I Hong
- Department of Neurosurgery, Roswell Park Cancer Institute, Buffalo, New York 14263, USA
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Vig R, Jain RK, Matta KL. Synthesis of methyl O-(beta-D-galactopyranosyl)-(1-->3)-O- [alpha-L-fucopyranosyl-(1-->4)]-2-acetamido-2-deoxy-6-O-sulfo-beta-D- glucopyranoside sodium salt as a potential ligand for selectin molecules. Carbohydr Res 1995; 266:279-84. [PMID: 7697659 DOI: 10.1016/0008-6215(94)00258-h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- R Vig
- Department of Gynecologic Oncology, Roswell Park Cancer Institute, Buffalo, NY 14263
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Hong CI, An SH, Nechaev A, Kirisits AJ, Vig R, West CR. Synthesis and antitumor activity of 1-beta-D-arabinofuranosylcytosine conjugates of optical isomers of ether and thioether lipids. Lipids 1993; 28:1021-6. [PMID: 8277825 DOI: 10.1007/bf02537125] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Four 1-beta-D-arabinofuranosylcytosine conjugates (ara-C) (1a, b and 2a, b) of sn-1 and sn-3 isomers of 1-O-octadecyl-2-O-palmitoylglycerol and its 1-S-alkyl analogue have been synthesized, and their antitumor activity against L1210 lymphoid leukemia in mice were compared with those of the previous conjugates (3a, b) of racemates in order to determine the significance of chirality of the glycerol moieties for activity. Administration (i.p.) of a single dose (300 mg/kg) of conjugates of sn-1 (1a), sn-3 (2a) and rac (3a) isomers of the ether lipid increased lifespan of i.p. implanted L1210 lymphoid leukemic DBA/2J mice by 169, 175 and 236%, respectively. The sn-1 (1b), sn-3 (2b), and rac (3b) isomers of the thioether lipid with a single dose of 300 mg/kg produced an increase in lifespan values of 238, 263 and 250%, respectively. The results indicate that chirality of the glycerol moieties appears not to be critical for the activity, and racemates 3a and 3b are promising prodrugs of ara-C for further clinical investigations.
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Affiliation(s)
- C I Hong
- Department of Neurosurgery, Roswell Park Cancer Institute, Buffalo, New York 14263
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Hong CI, Nechaev A, Kirisits AJ, Vig R, West CR. Nucleoside conjugates. 13. Synthesis and antitumor activity of 1-beta-D-arabinofuranosylcytosine conjugates of thioether lipids with improved water solubility. J Med Chem 1993; 36:1785-90. [PMID: 8510106 DOI: 10.1021/jm00064a012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A series of ara-CDP-rac-1-S-alkyl-2-O-acyl-1-thioglycerols (3-12), analogues of highly active Cytoros2 (1), was prepared, and solubility, lipophilicity, and structure-activity relationships of these conjugates were investigated. The conjugates with sn-1 alkyl (< C18) and sn-2 fatty acyl (< C14) substituents of the thioglycerol were water-soluble, while those with the sn-1 alkyl (> C14) and the sn-2 fatty acyl (> C16) were sparingly soluble. The latter formed micelles upon sonication. Conjugate 7 containing the sn-1 tetradecyl and the sn-2 palmitoyl (C16) groups formed micelles by both sonication and shaking. The partition coefficients (1-octanol/PBS) of the water-soluble conjugates were about 20 times greater than that of ara-C. The water-insoluble showed a more than 40 times increase. A single dose of the micelle-forming conjugates 7 and 10 produced a significant increase in life span (ILS > 421%) with 50% long-term survivors (> 45 days) in mice bearing ip-implanted L1210 lymphoid leukemia. These results were comparable to those of previous micelle-forming conjugate 1 (Cytoros). In contrast, the water-soluble conjugates at single doses were less effective (ILS 81-386% with 0-33% long-term survivors). However, three divided doses of the water-soluble conjugates were found to be as effective as a single dose of micellar solution of the water-insoluble. The results indicate that conjugate 7 and most of the water-soluble derivatives warrant further investigation.
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Affiliation(s)
- C I Hong
- Department of Neurosurgery, Roswell Park Cancer Institute, Buffalo, New York 14263
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Matta KL, Vig R, Abbas SA. Synthesis of 2-acetamido-2-deoxy-4-O-beta-D-galactopyranosyl-3-O-methyl -D-glucopyranose (N-acetyl-3-O-methyllactosamine) and its benzyl alpha-glycoside. Carbohydr Res 1984; 132:119-26. [PMID: 6488206 DOI: 10.1016/0008-6215(84)85069-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Benzyl 2-acetamido-2-deoxy-3-O-methyl-alpha-D-glucopyranoside (3) was obtained by deacetalation of its 4,6-O-benzylidene derivative (2). Compound 2 was prepared by methylation of benzyl 2-acetamido-4,6-O-benzylidene-2-deoxy-alpha-D-glucopyranoside with methyl iodide-silver oxide in N,N-dimethylformamide. Diol 3 was selectively benzoylated and p-toluenesulfonylated, to give the 6-benzoic and 6-p-toluenesulfonic esters (4 and 5, respectively). Displacement of the sulfonyl group of 5 with sodium benzoxide in benzyl alcohol afforded the 6-O-benzyl derivative (6). Glycosylation of 4 with 2,3,4,6-tetra-O-acetyl-alpha-D-galactopyranosyl bromide (7) in dichloromethane, in the presence of 1,1,3,3-tetramethylurea, furnished the disaccharide derivative 8. Similar glycosylation of compound 6 with bromide 7 gave the disaccharide derivative 10. O-Deacetylation of 8 and 10 afforded disaccharides 9 and 11. The structure of compound 9 was established by 13C-n.m.r. spectroscopy. Hydrogenolysis of the benzyl groups of 11 furnished the disaccharide 2-acetamido-2-deoxy-4-O-beta-D-galactopyranosyl-3-O-methyl-D-glucopyr ano se (N-acetyl-3-O-methyllactosamine).
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Vig R. UCLA at Whiteriver. Ariz Dent J 1972; 18:24-5 passim. [PMID: 4500346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Vig R. The heart of dentistry. Dental clinic for the Apaches. 2. CAL 1971; 34:6-7. [PMID: 5287338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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