3-Morpholino-7-[N-methyl-N-(4′-carboxyphenyl)amino]phenothiazinium Chloride

Round 1

Reviewer 1 Report

This paper descrives a simple and efficient synthesis of 3-morpholino-7-[N-methyl-N-(4’-carboxyphenyl)amino]phenothia zinium chloride.  Although the yields of each reaction in the introduction of substituents are not high, the application of various asymmetric compounds is expected. Therefore, the referee recommends acceptance of this work for Molbank after revising the following point.

If possible, data on the absorption spectrum of the title compound should be included. Also, if there are data showing that the morpholine unit contributes to limiting the aggregation tendency of the dye, that should be included as well.

The font of the text in the manuscript should be consistent. Roman font and Gothic font are mixed.

Author Response

If possible, data on the absorption spectrum of the title compound should be included. Also, if there are data showing that the morpholine unit contributes to limiting the aggregation tendency of the dye, that should be included as well.

We thank the referee for this comment. We added UV-vis spectra of a 2×10^-5 M solution of the title compound in H₂O, and in 1M NaCl solution. Both spectra are characterized by a broad and intense absorption band between 500 and 800 nm, which is typical of the monomeric form of phenothiazinium salts. Conversely, at the same concentration, other phenothiazinium salts, as methylene blue, shows the co-presence of the monomeric and dimeric species.