1
|
Ito Y, Tsutsui N, Osawa T, Hari Y. Synthesis of the Methyl Analog of 2′-O,4′-C-Ethylene-Bridged 5-Methyluridine via Intramolecular Radical Cyclization and Properties of Modified Oligonucleotides. J Org Chem 2019; 84:9093-9100. [DOI: 10.1021/acs.joc.9b01035] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Yuta Ito
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Nishihama, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Norika Tsutsui
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Nishihama, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Takashi Osawa
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Nishihama, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Yoshiyuki Hari
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Nishihama, Yamashiro-cho, Tokushima 770-8514, Japan
| |
Collapse
|
2
|
Nawale GN, Bahadorikhalili S, Sengupta P, Kadekar S, Chatterjee S, Varghese OP. 4′-Guanidinium-modified siRNA: a molecular tool to control RNAi activity through RISC priming and selective antisense strand loading. Chem Commun (Camb) 2019; 55:9112-9115. [DOI: 10.1039/c9cc04141a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We present synthesis, biochemical, biophysical and computational evaluation of 4′ gunanidino modified siRNA.
Collapse
Affiliation(s)
- Ganesh N. Nawale
- Translational Chemical Biology Laboratory
- Division of Polymer Chemistry
- Department of Chemistry-Ångström
- Uppsala University
- Uppsala
| | - Saeed Bahadorikhalili
- Translational Chemical Biology Laboratory
- Division of Polymer Chemistry
- Department of Chemistry-Ångström
- Uppsala University
- Uppsala
| | - Pallabi Sengupta
- Biomolecular NMR and Drug Design Laboratory
- Department of Biophysics
- Bose Institute
- Kolkata
- India
| | - Sandeep Kadekar
- Translational Chemical Biology Laboratory
- Division of Polymer Chemistry
- Department of Chemistry-Ångström
- Uppsala University
- Uppsala
| | - Subhrangsu Chatterjee
- Biomolecular NMR and Drug Design Laboratory
- Department of Biophysics
- Bose Institute
- Kolkata
- India
| | - Oommen P. Varghese
- Translational Chemical Biology Laboratory
- Division of Polymer Chemistry
- Department of Chemistry-Ångström
- Uppsala University
- Uppsala
| |
Collapse
|
3
|
Osawa T, Sawamura M, Wada F, Yamamoto T, Obika S, Hari Y. Synthesis, duplex-forming ability, enzymatic stability, and in vitro antisense potency of oligonucleotides including 2'-C,4'-C-ethyleneoxy-bridged thymidine derivatives. Org Biomol Chem 2018; 15:3955-3963. [PMID: 28440828 DOI: 10.1039/c7ob00698e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We synthesized thymidine derivatives of 2'-C,4'-C-ethyleneoxy-bridged 2'-deoxyribonucleic acids with an 8'-methyl group ((R)-Me-EoDNA and (S)-Me-EoDNA) and without any substituent (EoDNA). Oligonucleotides including these EoDNAs showed high hybridization abilities with complementary RNA and excellent enzymatic stabilities compared with natural DNA. Moreover, the in vitro antisense potency of oligonucleotides with these EoDNAs and our recently reported methylene-EoDNAs was investigated and compared with that of LNA, which is a practical chemical modification for oligonucleotide-therapeutic agents. The results showed that EoDNAs and methylene-EoDNAs could be promising candidates for antisense technology.
Collapse
Affiliation(s)
- Takashi Osawa
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Nishihama, Yamashiro-cho, Tokushima 770-8514, Japan.
| | | | | | | | | | | |
Collapse
|
4
|
Plashkevych O, Upadhayaya RS, Chattopadhyaya J. Carbocyclic C-C Bond Formation: Intramolecular Radical Ring Closure to Yield Diastereomerically Pure (7'S-Me- or 7'R-Me-) Carba-LNA Nucleotide Analogs. ACTA ACUST UNITED AC 2017. [PMID: 28628208 DOI: 10.1002/cpnc.29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In light of the impressive gene-silencing properties of carba-LNA modified oligo DNA and RNA, both in antisense RNA and siRNA approaches, which have been confirmed as proof-of-concept for biochemical applications in post-transcriptional gene silencing, we envision the true potential of carba-LNA modifications to be revealed soon. Herein we provide detailed protocols for synthesis of carba-LNA-A, -G, -5-Me C, and -T nucleosides on a medium/large scale (gram scale), as well as important guidelines for incorporation of these modified carba-LNAs into DNA or RNA oligonucleotides. Creation of a stereoselective C-C bond during the 5-exo radical intramolecular cyclization involves trapping of a C2' radical intermediate intramolecularly by the vicinal double bond of a C4'-tethered ─CH2 -CH═CH2 group. All diastereomers of substituted carba-LNAs are now available in pure form. The present procedure allows carba-LNA to be commercialized for medicinal or biotechnological purposes. © 2017 by John Wiley & Sons, Inc.
Collapse
Affiliation(s)
| | - Ram Shankar Upadhayaya
- Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden.,Bioimics AB, Uppsala, Sweden
| | | |
Collapse
|
5
|
Osawa T, Obika S, Hari Y. Synthesis and properties of novel 2′-C,4′-C-ethyleneoxy-bridged 2′-deoxyribonucleic acids with exocyclic methylene groups. Org Biomol Chem 2016; 14:9481-9484. [DOI: 10.1039/c6ob01960a] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Three methylene-EoDNAs were synthesized from 5-methyluridine and their modified oligonucleotides showed strong binding affinity with ssRNA and high nuclease resistance.
Collapse
Affiliation(s)
- Takashi Osawa
- Faculty of Pharmaceutical Sciences
- Tokushima Bunri University
- Tokushima 770-8514
- Japan
- Graduate School of Pharmaceutical Sciences
| | - Satoshi Obika
- Graduate School of Pharmaceutical Sciences
- Osaka University
- Osaka 565-0871
- Japan
| | - Yoshiyuki Hari
- Faculty of Pharmaceutical Sciences
- Tokushima Bunri University
- Tokushima 770-8514
- Japan
- Graduate School of Pharmaceutical Sciences
| |
Collapse
|
6
|
Yamamoto T, Yahara A, Waki R, Yasuhara H, Wada F, Harada-Shiba M, Obika S. Amido-bridged nucleic acids with small hydrophobic residues enhance hepatic tropism of antisense oligonucleotides in vivo. Org Biomol Chem 2015; 13:3757-65. [PMID: 25690587 DOI: 10.1039/c5ob00242g] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
High scalability of a novel bicyclic nucleoside building block, amido-bridged nucleic acid (AmNA), to diversify pharmacokinetic properties of therapeutic antisense oligonucleotides is described. N2'-functionalization of AmNA with a variety of hydrophobic groups is straightforward. Combinations of these modules display similar antisense knockdown effects and improve cellular uptake, relative to sequence-matched conventional 2',4'-bridged nucleic acid (2',4'-BNA) in vivo.
Collapse
Affiliation(s)
- Tsuyoshi Yamamoto
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | | | | | | | | | | | | |
Collapse
|
7
|
Osawa T, Hari Y, Dohi M, Matsuda Y, Obika S. Synthesis and Properties of the 5-Methyluridine Derivative of 3,4-Dihydro-2H-pyran-Bridged Nucleic Acid (DpNA). J Org Chem 2015; 80:10474-81. [PMID: 26431393 DOI: 10.1021/acs.joc.5b01425] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A novel 2'-O,4'-C-bridged nucleic acid, 3,4-dihydro-2H-pyran bridge moiety (DpNA), with a dioxabicyclo[3.2.1]oct-3-ene ring was designed. Construction of the dihydropyran bridge was achieved by dehydration of a six-membered hemiacetal ring, and the DpNA monomer was synthesized in 10 steps from 5-methyluridine (total yield 9%). The synthesized DpNA monomer was incorporated into oligonucleotides to examine the properties of the modified oligonucleotides. The DpNA-modified oligonucleotides possessed high affinity toward ssRNA and were more resistant to nucleases compared to the corresponding natural oligonucleotide.
Collapse
Affiliation(s)
- Takashi Osawa
- Graduate School of Pharmaceutical Sciences, Osaka University , 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan.,Core Research for Evolutional Science and Technology (CREST), Japan Sciences and Technology Agency (JST) , 7 Gobancho, Chiyoda-ku, Tokyo 102-0076, Japan
| | - Yoshiyuki Hari
- Graduate School of Pharmaceutical Sciences, Osaka University , 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan.,Faculty of Pharmaceutical Sciences, Tokushima Bunri University , Nishihama, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Masakazu Dohi
- Graduate School of Pharmaceutical Sciences, Osaka University , 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yuya Matsuda
- Graduate School of Pharmaceutical Sciences, Osaka University , 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Satoshi Obika
- Graduate School of Pharmaceutical Sciences, Osaka University , 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan.,Core Research for Evolutional Science and Technology (CREST), Japan Sciences and Technology Agency (JST) , 7 Gobancho, Chiyoda-ku, Tokyo 102-0076, Japan
| |
Collapse
|
8
|
Karimiahmadabadi M, Erfan S, Földesi A, Chattopadhyaya J. Distal Two-Bond versus Three-Bond Electronegative Oxo-Substituent Effect Controls the Kinetics and Thermodynamics of the Conversion of a C-Nitroso Function to the Corresponding Oxime in the Conformationally Locked Pentofuranose (Bicyclo[2.2.1]heptane) System. J Org Chem 2014; 79:7266-76. [DOI: 10.1021/jo500266k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Mansoureh Karimiahmadabadi
- Program of Chemical Biology,
Department of Cell and Molecular Biology, Biomedical Centre, Uppsala University, SE-75123 Uppsala, Sweden
| | - Sayeh Erfan
- Program of Chemical Biology,
Department of Cell and Molecular Biology, Biomedical Centre, Uppsala University, SE-75123 Uppsala, Sweden
| | - Andras Földesi
- Program of Chemical Biology,
Department of Cell and Molecular Biology, Biomedical Centre, Uppsala University, SE-75123 Uppsala, Sweden
| | - Jyoti Chattopadhyaya
- Program of Chemical Biology,
Department of Cell and Molecular Biology, Biomedical Centre, Uppsala University, SE-75123 Uppsala, Sweden
| |
Collapse
|
9
|
Kaura M, Kumar P, Hrdlicka PJ. Synthesis, hybridization characteristics, and fluorescence properties of oligonucleotides modified with nucleobase-functionalized locked nucleic acid adenosine and cytidine monomers. J Org Chem 2014; 79:6256-68. [PMID: 24933409 DOI: 10.1021/jo500994c] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Conformationally restricted nucleotides such as locked nucleic acid (LNA) are very popular as affinity-, specificity-, and stability-enhancing modifications in oligonucleotide chemistry to produce probes for nucleic acid targeting applications in molecular biology, biotechnology, and medicinal chemistry. Considerable efforts have been devoted in recent years to optimize the biophysical properties of LNA through additional modification of the sugar skeleton. We recently introduced C5-functionalization of LNA uridines as an alternative and synthetically more straightforward approach to improve the biophysical properties of LNA. In the present work, we set out to test the generality of this concept by studying the characteristics of oligonucleotides modified with four different C5-functionalized LNA cytidine and C8-functionalized LNA adenosine monomers. The results strongly suggest that C5-functionalization of LNA pyrimidines is indeed a viable approach for improving the binding affinity, target specificity, and/or enzymatic stability of LNA-modified ONs, whereas C8-functionalization of LNA adenosines is detrimental to binding affinity and specificity. These insights will impact the future design of conformationally restricted nucleotides for nucleic acid targeting applications.
Collapse
Affiliation(s)
- Mamta Kaura
- Department of Chemistry, University of Idaho , Moscow, Idaho 83844-2343, United States
| | | | | |
Collapse
|
10
|
Kumar P, Baral B, Anderson BA, Guenther DC, Østergaard ME, Sharma PK, Hrdlicka PJ. C5-alkynyl-functionalized α-L-LNA: synthesis, thermal denaturation experiments and enzymatic stability. J Org Chem 2014; 79:5062-73. [PMID: 24797769 PMCID: PMC4049248 DOI: 10.1021/jo5006153] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Indexed: 12/23/2022]
Abstract
Major efforts are currently being devoted to improving the binding affinity, target specificity, and enzymatic stability of oligonucleotides used for nucleic acid targeting applications in molecular biology, biotechnology, and medicinal chemistry. One of the most popular strategies toward this end has been to introduce additional modifications to the sugar ring of affinity-inducing conformationally restricted nucleotide building blocks such as locked nucleic acid (LNA). In the preceding article in this issue, we introduced a different strategy toward this end, i.e., C5-functionalization of LNA uridines. In the present article, we extend this strategy to α-L-LNA: i.e., one of the most interesting diastereomers of LNA. α-L-LNA uridine monomers that are conjugated to small C5-alkynyl substituents induce significant improvements in target affinity, binding specificity, and enzymatic stability relative to conventional α-L-LNA. The results from the back-to-back articles therefore suggest that C5-functionalization of pyrimidines is a general and synthetically straightforward approach to modulate biophysical properties of oligonucleotides modified with LNA or other conformationally restricted monomers.
Collapse
Affiliation(s)
- Pawan Kumar
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
- Department of Chemistry, Kurukshetra University, Kurukshetra 136119, India
| | - Bharat Baral
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
| | - Brooke A. Anderson
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
| | - Dale C. Guenther
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
| | - Michael E. Østergaard
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
| | - Pawan K. Sharma
- Department of Chemistry, Kurukshetra University, Kurukshetra 136119, India
| | - Patrick J. Hrdlicka
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
| |
Collapse
|
11
|
Kumar P, Østergaard ME, Baral B, Anderson BA, Guenther DC, Kaura M, Raible DJ, Sharma PK, Hrdlicka PJ. Synthesis and biophysical properties of C5-functionalized LNA (locked nucleic acid). J Org Chem 2014; 79:5047-61. [PMID: 24825249 PMCID: PMC4049237 DOI: 10.1021/jo500614a] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Indexed: 01/07/2023]
Abstract
Oligonucleotides modified with conformationally restricted nucleotides such as locked nucleic acid (LNA) monomers are used extensively in molecular biology and medicinal chemistry to modulate gene expression at the RNA level. Major efforts have been devoted to the design of LNA derivatives that induce even higher binding affinity and specificity, greater enzymatic stability, and more desirable pharmacokinetic profiles. Most of this work has focused on modifications of LNA's oxymethylene bridge. Here, we describe an alternative approach for modulation of the properties of LNA: i.e., through functionalization of LNA nucleobases. Twelve structurally diverse C5-functionalized LNA uridine (U) phosphoramidites were synthesized and incorporated into oligodeoxyribonucleotides (ONs), which were then characterized with respect to thermal denaturation, enzymatic stability, and fluorescence properties. ONs modified with monomers that are conjugated to small alkynes display significantly improved target affinity, binding specificity, and protection against 3'-exonucleases relative to regular LNA. In contrast, ONs modified with monomers that are conjugated to bulky hydrophobic alkynes display lower target affinity yet much greater 3'-exonuclease resistance. ONs modified with C5-fluorophore-functionalized LNA-U monomers enable fluorescent discrimination of targets with single nucleotide polymorphisms (SNPs). In concert, these properties render C5-functionalized LNA as a promising class of building blocks for RNA-targeting applications and nucleic acid diagnostics.
Collapse
Affiliation(s)
- Pawan Kumar
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
- Department of Chemistry, Kurukshetra University, Kurukshetra 136119, India
| | - Michael E. Østergaard
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
| | - Bharat Baral
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
| | - Brooke A. Anderson
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
| | - Dale C. Guenther
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
| | - Mamta Kaura
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
| | - Daniel J. Raible
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
| | - Pawan K. Sharma
- Department of Chemistry, Kurukshetra University, Kurukshetra 136119, India
| | - Patrick J. Hrdlicka
- Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, United States
| |
Collapse
|
12
|
Andersen NK, Anderson BA, Wengel J, Hrdlicka PJ. Synthesis and characterization of oligodeoxyribonucleotides modified with 2'-amino-α-L-LNA adenine monomers: high-affinity targeting of single-stranded DNA. J Org Chem 2013; 78:12690-702. [PMID: 24304240 DOI: 10.1021/jo4022937] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The development of conformationally restricted nucleotide building blocks continues to attract considerable interest because of their successful use within antisense, antigene, and other gene-targeting strategies. Locked nucleic acid (LNA) and its diastereomer α-L-LNA are two interesting examples thereof. Oligonucleotides modified with these units display greatly increased affinity toward nucleic acid targets, improved binding specificity, and enhanced enzymatic stability relative to unmodified strands. Here we present the synthesis and biophysical characterization of oligodeoxyribonucleotides (ONs) modified with 2'-amino-α-L-LNA adenine monomers W-Z. The synthesis of the target phosphoramidites 1-4 is initiated from pentafuranose 5, which upon Vorbrüggen glycosylation, O2'-deacylation, O2'-activation and C2'-azide introduction yields nucleoside 8. A one-pot tandem Staudinger/intramolecular nucleophilic substitution converts 8 into 2'-amino-α-L-LNA adenine intermediate 9, which after a series of nontrivial protecting-group manipulations affords key intermediate 15. Subsequent chemoselective N2'-functionalization and O3'-phosphitylation give targets 1-4 in ~1-3% overall yield over 11 steps from 5. ONs modified with pyrene-functionalized 2'-amino-α-L-LNA adenine monomers X-Z display greatly increased affinity toward DNA targets (ΔTm/modification up to +14 °C). Results from absorption and fluorescence spectroscopy suggest that the duplex stabilization is a result of pyrene intercalation. These characteristics render N2'-pyrene-functionalized 2'-amino-α-L-LNAs of considerable interest for DNA-targeting applications.
Collapse
Affiliation(s)
- Nicolai K Andersen
- Nucleic Acid Center, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , 5230 Odense, Denmark
| | | | | | | |
Collapse
|
13
|
Karimiahmadabadi M, Földesi A, Chattopadhyaya J. Unusual strain-releasing nucleophilic rearrangement of a bicyclo[2.2.1]heptane system to a cyclohexenyl derivative. J Org Chem 2012; 77:9747-55. [PMID: 23062056 DOI: 10.1021/jo301871d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We report an unusual strain-releasing reaction of 1-mesyloxy-8,7-dimethylbicyclo[2.2.1]heptane (3) by a base-promoted substitution at the chiral C3 followed by spontaneous concerted ring opening involving the most strained C2-C3-C4 bonds (with bond angle 94°) and the C2 bridgehead leading to anti-endo elimination of the C1-mesyloxy group by the conjugate base of adenine or thymine to give two diastereomeric C3'(S) and C3'(R) derivatives of 1-thyminyl and 9-adeninyl cyclohexene: 3 → T-4a + T-4b and 3 → A-5a + A-5b. These products have been unambiguously characterized by detailed 1D and 2D NMR (J-coupling constants and nOe analysis), mass, and UV spectroscopy. Evidence has been presented suggesting that the origin of these diastereomeric C3'(S) and C3'(R) derivatives of 1-thyminyl and 9-adeninyl cyclohexene from 3 is most probably a rearrangement mechanism of a trigonal bipyramidal intermediate formed in the S(N)2 displacement-ring-opening reaction.
Collapse
Affiliation(s)
- Mansoureh Karimiahmadabadi
- Program of Chemical Biology, Department of Cell and Molecular Biology, Biomedical Centre, Uppsala University, SE-75123 Uppsala, Sweden
| | | | | |
Collapse
|
14
|
Karimiahmadabadi M, Erfan S, Földesi A, Chattopadhyaya J. Steric Effects in the Tuning of the Diastereoselectivity of the Intramolecular Free-Radical Cyclization to an Olefin As Exemplified through the Synthesis of a Carba-Pentofuranose Scaffold. J Org Chem 2012; 77:6855-72. [DOI: 10.1021/jo300936g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Mansoureh Karimiahmadabadi
- Program of
Chemical Biology, Department of Cell and
Molecular Biology, Biomedical Centre, Uppsala University, SE-75123 Uppsala, Sweden
| | - Sayeh Erfan
- Program of
Chemical Biology, Department of Cell and
Molecular Biology, Biomedical Centre, Uppsala University, SE-75123 Uppsala, Sweden
| | - Andras Földesi
- Program of
Chemical Biology, Department of Cell and
Molecular Biology, Biomedical Centre, Uppsala University, SE-75123 Uppsala, Sweden
| | - Jyoti Chattopadhyaya
- Program of
Chemical Biology, Department of Cell and
Molecular Biology, Biomedical Centre, Uppsala University, SE-75123 Uppsala, Sweden
| |
Collapse
|
15
|
Zhou C, Chattopadhyaya J. Intramolecular free-radical cyclization reactions on pentose sugars for the synthesis of carba-LNA and carba-ENA and the application of their modified oligonucleotides as potential RNA targeted therapeutics. Chem Rev 2012; 112:3808-32. [PMID: 22530946 DOI: 10.1021/cr100306q] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Chuanzheng Zhou
- Chemical Biology Program, Department of Cell and Molecular Biology, Biomedical Center, Uppsala University, Sweden
| | | |
Collapse
|
16
|
Loakes D. Nucleotides and nucleic acids; oligo- and polynucleotides. ORGANOPHOSPHORUS CHEMISTRY 2012. [DOI: 10.1039/9781849734875-00169] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- David Loakes
- Medical Research Council Laboratory of Molecular Biology, Hills Road Cambridge CB2 2QH UK
| |
Collapse
|
17
|
Nicolaou KC, Ellery SP, Rivas F, Saye K, Rogers E, Workinger TJ, Schallenberger M, Tawatao R, Montero A, Hessell A, Romesberg F, Carson D, Burton D. Synthesis and biological evaluation of 2',4'- and 3',4'-bridged nucleoside analogues. Bioorg Med Chem 2011; 19:5648-69. [PMID: 21840722 PMCID: PMC3348725 DOI: 10.1016/j.bmc.2011.07.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 07/12/2011] [Accepted: 07/13/2011] [Indexed: 10/18/2022]
Abstract
Most nucleosides in solution typically exist in equilibrium between two major sugar pucker forms, N-type and S-type, but bridged nucleosides can be locked into one of these conformations depending on their specific structure. While many groups have researched these bridged nucleosides for the purpose of determining their binding affinity for antisense applications, we opted to look into the potential for biological activity within these conformationally-locked structures. A small library of 2',4'- and 3',4'-bridged nucleoside analogues was synthesized, including a novel 3',4'-carbocyclic bridged system. The synthesized compounds were tested for antibacterial, antitumor, and antiviral activities, leading to the identification of nucleosides possessing such biological activities. To the best of our knowledge, these biologically active compounds represent the first example of 2',4'-bridged nucleosides to demonstrate such properties. The most potent compound, nucleoside 33, exhibited significant antiviral activity against pseudoviruses SF162 (IC(50)=7.0 μM) and HxB2 (IC(50)=2.4 μM). These findings render bridged nucleosides as credible leads for drug discovery in the anti-HIV area of research.
Collapse
Affiliation(s)
- K C Nicolaou
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Mori K, Kodama T, Baba T, Obika S. Bridged nucleic acid conjugates at 6'-thiol: synthesis, hybridization properties and nuclease resistances. Org Biomol Chem 2011; 9:5272-9. [PMID: 21643564 DOI: 10.1039/c1ob05469d] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The bridged nucleic acid (BNA) containing a thiol at the 6'-position in the bridged structure was synthesized from the disulfide-type BNA and conjugated with various functional molecules via the thioether or the disulfide linkage post-synthetically and efficiently in solution phase. The disulfide-linked conjugate was cleaved under reductive conditions derived from glutathione and an oligonucleotide bearing a free thiol was released smoothly. Conjugated functional molecules had great effects on duplex stability with the DNA complement. In contrast, the molecules little influenced the stability with the RNA complement. Moreover, the oligonucleotides with functional groups at the 6'-position had as high or higher resistances against 3'-exonuclease than phosphorothioate oligonucleotide (S-oligo).
Collapse
Affiliation(s)
- Kazuto Mori
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan
| | | | | | | |
Collapse
|
19
|
Upadhayaya R, Deshpande SG, Li Q, Kardile RA, Sayyed AY, Kshirsagar EK, Salunke RV, Dixit SS, Zhou C, Földesi A, Chattopadhyaya J. Carba-LNA-5MeC/A/G/T modified oligos show nucleobase-specific modulation of 3'-exonuclease activity, thermodynamic stability, RNA selectivity, and RNase H elicitation: synthesis and biochemistry. J Org Chem 2011; 76:4408-31. [PMID: 21500818 DOI: 10.1021/jo200073q] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Using the intramolecular 5-exo-5-hexenyl radical as a key cyclization step, we previously reported an unambiguous synthesis of carba-LNA thymine (cLNA-T), which we subsequently incorporated in antisense oligonucleotides (AON) and investigated their biochemical properties [J. Am. Chem. Soc.2007, 129 (26), 8362-8379]. These cLNA-T incorporated oligos showed specific RNA affinity of +3.5-5 °C/modification for AON:RNA heteroduplexes, which is comparable to what is found for those of LNAs (Locked Nucleic Acids). These modified oligos however showed significantly enhanced nuclease stability (ca. 100 times more) in the blood serum compared to those of the LNA modified counterparts without compromising any RNase H recruitment capability. We herein report the synthesis of 5-methylcytosine-1-yl ((Me)C), 9-adeninyl (A), and 9-guaninyl (G) derivatives of cLNA and their oligonucleotides and report their biochemical properties as potential RNA-directed inhibitors. In a series of isosequential carba-LNA modified AONs, we herein show that all the cLNA modified AONs are found to be RNA-selective, but the magnitude of RNA-selectivity of 7'-R-Me-cLNA-G (cLNA-G) (ΔT(m) = 2.9 °C/modification) and intractable isomeric mixtures of 7'-(S/R)-Me-cLNA-T (cLNA-T, ΔT(m) = 2.2 °C/modification) was found to be better than diastereomeric mixtures of 7'-(S/R)-Me-cLNA-(Me)C with trace of cENA-(Me)C (cLNA-(Me)C, ΔT(m) = 1.8 °C/modification) and 7'-R-Me-cLNA-A (cLNA-A, ΔT(m) = 0.9 °C/modification). cLNA-(Me)C modified AONs however exhibited the best nuclease stability, which is 4-, 7-, and 20-fold better, respectively, than cLNA-T, cLNA-A, and cLNA-G modified counterparts, which in turn was more than 100 times stable than that of the native. When the modification sites are appropriately chosen in the AONs, the cLNA-A, -G, and -(Me)C modified sites in the AON:RNA hybrids can be easily recognized by RNase H, and the RNA strand of the hybrid is degraded in a specific manner, which is important for the design of oligos for therapeutic purposes. The cLNA-(Me)C modified AON/RNA, however, has been found to be degraded 4 times faster than cLNA-A and G modified counterparts. By appropriately choosing the carba-LNA modification sites in AON strands, the digestion of AON:RNA can be either totally repressed or be limited to cleavage at specific sites or at a single site only (similar to that of catalytic RNAzyme or DNAzyme). Considering all physico- and biochemical aspects of cLNA modified oligos, the work suggests that the cLNA modified antisense oligos have the potential of being a promising therapeutic candidate due to their (i) higher nucleobase-specific RNA affinity and RNA selectivity, (ii) greatly improved nuclease stability, and (iii) efficient RNase H recruitment capability, which can induce target RNA cleavage in a very specific manner at multiple or at a single site, in a designed manner.
Collapse
Affiliation(s)
- RamShankar Upadhayaya
- Institute of Molecular Medicine, International Biotech Park, Tal Mulshi, Hinjewadi, Pune, India
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Kannan A, Burrows CJ. Synthesis of N2-alkyl-8-oxo-7,8-dihydro-2'-deoxyguanosine derivatives and effects of these modifications on RNA duplex stability. J Org Chem 2010; 76:720-3. [PMID: 21192638 DOI: 10.1021/jo102187y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
N(2)-alkyl analogues of 8-oxo-7,8-dihydro-2'-deoxyguanosine (OG) were synthesized (alkyl = propyl, benzyl) via reductive amination of the protected OG nucleoside and incorporated into various positions of an RNA strand. Thermal stability studies of duplexes containing A or C opposite a single modified base revealed only moderate destabilization. Both OG as well as its N(2)-alkyl analogues can pair opposite A or C with nearly equal stability, potentially offering a new means of modulating RNA-protein interactions in the minor vs major grooves.
Collapse
Affiliation(s)
- Arunkumar Kannan
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, United States
| | | |
Collapse
|