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Abstract Mono‐ andbis‐decylated lumazines have been synthesized and characterized. Namely,mono‐decyl chain [1‐decylpteridine‐2,4(1,3H)‐dione]6aandbis‐decyl chain [1,3‐didecylpteridine‐2,4(1,3H)‐dione]7aconjugates were synthesized by nucleophilic substitution (SN2) reactions of lumazine with 1‐iododecane inN,N‐dimethylformamide (DMF) solvent. Decyl chain coupling occurred at theN1site and then theN3site in a sequential manner, without DMF condensation. Molecular orbital (MO) calculations show ap‐orbital atN1but notN3, which along with a nucleophilicity parameter (N) analysis predict alkylation atN1in lumazine. Only after the alkylation atN1in6a, does ap‐orbital onN3emerge thereby reacting with a second equivalent of 1‐iododecane to reach the dialkylated product7a. Data from NMR (1H,13C, HSQC, HMBC), HPLC, TLC, UV‐vis, fluorescence and density functional theory (DFT) provide evidence for the existence ofmono‐decyl chain6aandbis‐decyl chain7a. These results differ to pterinO‐alkylations (kinetic control), whereN‐alkylation of lumazine is preferred and then to dialkylation (thermodynamic control), with an avoidance of DMF solvent condensation. These findings add to the list of alkylation strategies for increasing sensitizer lipophilicity for use in photodynamic therapy.
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Mono‐ O ‐functionalizations of Pittsburgh Green and Their Applications
Abstract The previous synthetic strategy for the preparation of non‐fluorescent fluoresceins was mostly limited to the double addition of simple alkenes and alkynes. We report the one‐step masking of Pittsburgh Green to its mono‐alkylated or esterified compounds. Unlike previous syntheses, this strategy tolerates a broader range of functional groups as masking groups. We also demonstrate the advantage of mono‐alkylation over di‐alkylation for metal detection.
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- Award ID(s):
- 1955758
- PAR ID:
- 10445198
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- European Journal of Organic Chemistry
- Volume:
- 2022
- Issue:
- 22
- ISSN:
- 1434-193X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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