5-Bromo-N′-(2-oxoindolin-3-ylidene)furan-2-carbohydrazide

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Review-Molbank 5-Bromo-N'-(2-oxoindolin-3-ylidene)furan-2-carbohydrazide

This article describes the synthesis of 5-Bromo-N'-(2-oxoindolin-3-ylidene)furan-2-carbohydrazide, a compound of some medical interest, in particular it’s interaction with the COX-2 enzyme.

The synthesis is fairly routine. This compound is commercially available but surprisingly has not been published, but other variants have.  

The English is sufficient for publication purposes however the was one typo in all places…the abstract. I have highlighted some improvements to the article written language.

As written: -5-Bromo-N'-(2-oxoindolin-3-ylidene)furan-2-carbohydrazide (1) was successfully synthesized in 81% yield isatin and 5-bromofuran-2-carbohydrazide in acidic conditions under reflux.

Correction: 5-Bromo-N'-(2-oxoindolin-3-ylidene)furan-2-carbohydrazide (1) was successfully synthesized in 81% yield by reaction of isatin with 5-bromofuran-2-carbohydrazide in acidic conditions under reflux.

 As written: The expected product was filtered and washed using dichloromethane to get compound 1 as a yellowish solid 44 in 81% yield.

Correction: The expected product was filtered and washed using dichloromethane to isolate compound 1 as a yellowish solid 44 in 81% yield.

A discussion on the 13C NMR would be useful especially assignment of the  broad resonances and the source of the broodening.

Materials and methods:

Add city and country of instrument manufacturer

I am fairly certain that the IR stretch at 1680 is not a C=N stretch but instead a C=O stretch

A HETCOR or HSQC could be useful in assigning the broad ¹³C NMR resonances. This would at least provide more interesting aspects to the compound since the 1H NRM of it is available online. This would also allow for a more accurate assignment of the 1H and 13C NMR spectra.

Supporting Information

All deuterated solvents need to be added to the figure caption of NMR spectra.

Provide blow up of aromatic portion of the NMR

Provide better resolution spectra

Add IR technique (Nujol, Salt plate, ATR, HATR)

 

If interested parties want to synthesize this compound a better suited article would be to access the following journal article, Der Pharma Chemica, 2014, 6(1):272-278 which provides the same synthesis of similar molecules without the use of sulfuric acid, which is both safer and less hazardous waste.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Although the manuscript describes a very elementary and classical chemical reaction, the title compound has not been reported previously.

Therefore the manuscript might be published on Molbank.

I have the following minor points

 

1.        When the full name of the compound is written, the brackets are usually in plain text, not bold.

For example: 5-bromo-N'-(2-oxoindolin-3-ylidene)furan-32 2-carbohydrazide (1).

2.        The amount of H₂SO₄ used should be added. Catalytical amount is too vague.

3.        Is not clear if the reaction time is 15 minutes or longer. “After the reaction is complete” should be deleted if the reaction time was exactly 15 minutes.

4.        Ethyl asetate

5.        130 mg of the title compound furnish 79.4% yield.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

·         Since the authors have not corrected the concerns in the previous review, I will add them here again:

·         A HETCOR or HSQC could be useful in assigning the broad ¹³C NMR resonances. This would at least provide more interesting aspects to the compound since the 1H NMR of it is available online. This would also allow for a more accurate assignment of the 1H and 13C NMR spectra.

·         This compound is commercially available. The authors need to include references on how compounds 2 and 3 are prepared with the citation placed in the correct locations.

·         In addition, there need to be referencing the NMR assignment and how they compare to similar compounds.  

·         There are a number of typos that need to be corrected before publishing such as

·         “ indicated that compound 1 has the potential to be optimized 13 into an anti-inflammatory agent”

·         The commas in the decimal place in the experimental needs to be replaced with periods.

·         In the discussion of the NMR, “Meanwhile, the NH of the isatin ring was detected as a singlet signal at δ 11.30 ppm.”  The authors need to state the technique …1H NMR?

·         Meanwhile should not be used. It is a reference of time. In this case they should just use while.

 

Supporting Information

·         All deuterated solvents need to be added to the figure caption of NMR spectra.

·         Provide blow up of aromatic portion of the NMR

·         Provide better resolution spectra

 

·         Add IR technique (Nujol, Salt plate, ATR, HATR)

Comments on the Quality of English Language

The English is ok. 

Author Response

Please see the attachment

Author Response File: Author Response.pdf