<i>meso</i>‐Modified Cobalamins: Synthesis, Structure, and Properties

Wierzba, Aleksandra J.; Wincenciuk, Aleksandra; Karczewski, Maksymilian; Vullev, Valentine I.; Gryko, Dorota

doi:10.1002/chem.201801807

Cited by 15 publications

(13 citation statements)

References 55 publications

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“…In 2018, a straightforward and efficient synthesis of meso ‐functionalized cobalamins was reported . This involves nitration at the meso (C10) position of (CN)Cbl ( 1 a ) to give (CN)Cbl‐(10‐NO 2 ) 22 that is subsequently reduced with NaBH 4 to amino derivative 23 (Scheme ).…”

Section: Conjugation At the Macrocyclic Corementioning

confidence: 99%

Synthetic Approaches toward Vitamin B₁₂ Conjugates

2018

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The ability to conjugate functional molecules to vitamin B 12 (cobalamin) is an important strategy for the construction of hybrid molecules with various applications in medicinal chemistry, diagnostics, and biological sciences. Cobalamin, as an exogenous compound, reaches mammalian cells via a system of transport proteins and therefore the position of conjugation must be selected in such a way that the recognition process is not disturbed. The complex structure of vitamin B 12 provides many routes for the synthesis of conjugates containing cargos appended at different sites, however, only the e-propionamide chain, βaxial position and R 5' -OH are found to meet the aforementioned criteria. Over the years, a number of synthetic approaches leading to cobalamin conjugates have been developed and, herein, we summarize those leading to conjugates with a cargo tethered at the central cobalt ion, macrocyclic core, ribonucleotide moiety, or a combination thereof. . Synthesis of cobalamin triazoles. Scheme 16. Synthesis of precursor 41 and its subsequent functionalization. Scheme 17. Functionalization of phosphate moiety.[a] Compound 43 c was obtained from 43 b via substitution with NaN 3 .

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Section: Conjugation At the Macrocyclic Corementioning

confidence: 99%

Synthetic Approaches toward Vitamin B₁₂ Conjugates

2018

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“…A similar strategy can be utilized for functionalization at the e position by employing the (CN)Cbl‐ epi ‐( e ‐lactone) ( 12 ) as a starting material (Scheme B ). This compound forms as the main byproduct during the nitration of Cbl 1 . The subsequent reduction of e ‐lactone 12 with NaBH 4 gives (CN)Cbl‐ epi ‐( e ‐COOH) ( 13 ) in 65 % yield, which, after coupling with aminoazide 3 in the presence of HBTU/HOBt, gives e ‐amide 14 in good yield.…”

Section: Resultsmentioning

confidence: 99%

“…This compound forms as the main byproduct during the nitration of Cbl 1. [50] The subse-quent reduction of e-lactone 12 with NaBH 4 gives (CN)Cbl-epi-(e-COOH) (13)i n6 5% yield, which, after coupling with aminoazide 3 in the presence of HBTU/HOBt, gives e-amide 14 in good yield.…”

Section: Synthesis Of Cbl Azidesmentioning

confidence: 99%

“…In the next step, we planned to attach PNA at the meso position.T ot his end, we reacted recently described (CN)Cbl(10-NH 2 )( 15) [50] with suitably functionalized benzaldehydes (Scheme 4 A)a nd obtained imines 16 and 17 with terminal groups suitable for further transformations.H owever,t he imine bond suffers from limited stability in the bacterial medium. To overcome this issue, we first reduced imine 17,w ith at erminal Ts group, to secondary amine 18.…”

Section: Synthesis Of Cbl Azidesmentioning

confidence: 99%

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Does a Conjugation Site Affect Transport of Vitamin B₁₂–Peptide Nucleic Acid Conjugates into Bacterial Cells?

Wierzba

Maximova

Wincenciuk

et al. 2018

Chemistry A European J

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Gram‐negative bacteria develop specific systems for the uptake of scarce nutrients, including vitamin B12. These uptake pathways may be utilized for the delivery of biologically relevant molecules into cells. Indeed, it was recently reported that vitamin B12 transported an antisense peptide nucleic acid (PNA) into Escherichia coli and Salmonella Typhimurium cells. The present studies indicate that the conjugation site of PNA to vitamin B12 has an impact on PNA transport into bacterial cells. Toward this end, a specifically designed PNA oligomer has been tethered at various positions of vitamin B12 (central Co, R5′‐OH, c and e amide chains, meso position, and at the hydroxy group of cobinamide) by using known or newly developed methodologies and tested for the uptake of the synthesized conjugates by E. coli. Compounds in which the PNA oligonucleotide was anchored at the R5′‐OH position were transported more efficiently than that of other compounds tethered at the peripheral positions around the corrin ring. Of importance is the fact that, contrary to mammalian organisms, E. coli also takes up cobinamide, which is an incomplete corrinoid. This selectivity opens up ways to fight bacterial infections.

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“…Therefore, biological inspiration provides routes for overcoming the inherent limitations of the living systems. Bioinspired approaches involve taking ideas and elements from biology and implementing them in manners different from their natural occurrence [1,[111][112][113]. For example, materials genome has nothing to do with DNA or other information-carrying biomolecules.…”

Section: General Considerations Biomimetic Vs Bioinspired What's Thmentioning

confidence: 99%

Biomimetic and bioinspired molecular electrets. How to make them and why does the established peptide chemistry not always work?

Skonieczny

Espinoza

Derr

et al. 2019

Pure and Applied Chemistry

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Abstract“Biomimetic” and “bioinspired” define different aspects of the impacts that biology exerts on science and engineering. Biomimicking improves the understanding of how living systems work, and builds tools for bioinspired endeavors. Biological inspiration takes ideas from biology and implements them in unorthodox manners, exceeding what nature offers. Molecular electrets, i.e. systems with ordered electric dipoles, are key for advancing charge-transfer (CT) science and engineering. Protein helices and their biomimetic analogues, based on synthetic polypeptides, are the best-known molecular electrets. The inability of native polypeptide backbones to efficiently mediate long-range CT, however, limits their utility. Bioinspired molecular electrets based on anthranilamides can overcome the limitations of their biological and biomimetic counterparts. Polypeptide helices are easy to synthesize using established automated protocols. These protocols, however, fail to produce even short anthranilamide oligomers. For making anthranilamides, the residues are introduced as their nitrobenzoic-acid derivatives, and the oligomers are built from their C- to their N-termini via amide-coupling and nitro-reduction steps. The stringent requirements for these reduction and coupling steps pose non-trivial challenges, such as high selectivity, quantitative yields, and fast completion under mild conditions. Addressing these challenges will provide access to bioinspired molecular electrets essential for organic electronics and energy conversion.

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meso‐Modified Cobalamins: Synthesis, Structure, and Properties

Cited by 15 publications

References 55 publications

Synthetic Approaches toward Vitamin B₁₂ Conjugates

Synthetic Approaches toward Vitamin B₁₂ Conjugates

Does a Conjugation Site Affect Transport of Vitamin B₁₂–Peptide Nucleic Acid Conjugates into Bacterial Cells?

Biomimetic and bioinspired molecular electrets. How to make them and why does the established peptide chemistry not always work?

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meso‐Modified Cobalamins: Synthesis, Structure, and Properties

Cited by 15 publications

References 55 publications

Synthetic Approaches toward Vitamin B12 Conjugates

Synthetic Approaches toward Vitamin B12 Conjugates

Does a Conjugation Site Affect Transport of Vitamin B12–Peptide Nucleic Acid Conjugates into Bacterial Cells?

Biomimetic and bioinspired molecular electrets. How to make them and why does the established peptide chemistry not always work?

Contact Info

Product

Resources

About

Synthetic Approaches toward Vitamin B₁₂ Conjugates

Synthetic Approaches toward Vitamin B₁₂ Conjugates

Does a Conjugation Site Affect Transport of Vitamin B₁₂–Peptide Nucleic Acid Conjugates into Bacterial Cells?