Synthesis and Antimicrobial Activities of some Quaternary Morpholinium Chlorides

Abstract

The synthesis and antimicrobial activity of 31 morpholinium chlorides, divided into five series depending on the substituents attached to the nitrogen atom, N-carboxyalkyl-morpholinium chlorides (1a-e), N-carbalkoxymethyl-N-methyl-morpholinium chlorides (2a-f), N-carbethoxymethyl-N-alkyl-morpholinium chlorides (3a-g), N-carbalkoxymethyl-N-dodecyl-morpholinium chlorides (4a-f) and N-carboxymethyl-N-alkyl-morpholinium chlorides (5a-g) is reported. The compounds investigated were tested for antimicrobial activity against Staphylococcus aureus, Escherichia coli, Proteus vulgaris, Pseudomonas aeruginosa, Candida albicans and Trichophyton menthagrophytes. The most active are compounds with a long N-alkyl group and with the substituent CH2COOC(n)H(2n-1) (n = 8-16).

General acid catalysis in benzoic acid–Crystal Violet carbinol base reactions in toluene

“…As seen, values of n are close to or greater than unity. A similar behavior was observed for many other acids in apolar aprotic solvents 2–24. This has been ascribed to overlapping participations of open chain dimeric and multimeric homoconjugated complex acids H(A⋅⋅⋅(HA) m ( m ≥1) in the reaction with the carbinol base (D) in apolar aprotic media 2–24.…”

“…(1)) is hydrogen bonded to one of the species of system and that they exist as one entity 25. Taking into consideration the possibility of HA existing not simply as a monomer but effectively as a n ‐mer due to formation of reactive open chain (homoconjugated acid–acid anion complex acids) and nonreactive cyclic acid multimers in toluene, the apolar aprotic solvent 20–24, Eq. (1), can be reexpressed as where D and DH + n A − n represent the colorless carbinol base of Crystal Violet and the colored ion associate, respectively.…”

“…This has been ascribed to overlapping participations of open chain dimeric and multimeric homoconjugated complex acids H(A⋅⋅⋅(HA) m ( m ≥1) in the reaction with the carbinol base (D) in apolar aprotic media 2–24. The value of the acid exponent ( n ) for an acid depends upon its concentration, temperature, and solvent 10,17–24.…”

“…The variation, however, did not follow any simple pattern, indicating the occurrence of general acid catalysis, an acid playing the dual role of the substrate and the catalyst 2–4,7–14. The complex k versus C HA variation is not unexpected in view of the possibility of HA existing as a hyperacidic homoconjugated complex acid, H(A⋅⋅⋅(HA) m ( m ≥ 1), a nonreactive cyclic dimer (HA) 2 , etc., besides the monomeric HA in an apolar aprotic medium 2–24. The k versus C HA variation has been probed in detail to determine the constants of catalysis by such different acidic species for a series of 23 meta‐ and ortho‐substituted benzoic acids in their toluene‐phase reactions with Crystal Violet carbinol base, the reference base.…”

Synthesis, toxicity, biodegradability and physicochemical properties of 4-benzyl-4-methylmorpholinium-based ionic liquids

“…This was confirmed by tests on the antimicrobial activity of 4-carbalkoxymethyl-4-methylmorpholinium chlorides. 38 The cytotoxicity of the compounds synthesized to the IPC 81 rat leukaemia cell line is summarized in Table 5. We used the concept of "anion effect ratio" to classify relative toxicities of anions in ILs.…”