Synthesis of Novel Thiazoles Based on (+)-Usnic Acid

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The Ms. “Synthesis of novel thiazoles based on (+)-usnic acid” describes the synthesis a series of usnic acid derivatives containing a thiazole ring with an amide substituent.

In my opinion the work can be published after the authors answer the following questions,

-       In Scheme 1, in the Result and Discussion section, the authors must be explain the reason why the acylation reaction of usnic acid derivative with benzoyl chloride in the present of triethylaminedid not lead to the production of the target derivative

-       The first part of Scheme 2, although well know, needs to be better explained

The Ms. may be published in Molbank Journal Communications with minor corrections

Author Response

Dear Reviewer,

Thank you for reading our article and for Your helpful comments!

Comment 1: In Scheme 1, in the Result and Discussion section, the authors must be explain the reason why the acylation reaction of usnic acid derivative with benzoyl chloride in the present of triethylaminedid not lead to the production of the target derivative.

Response 1: We've supplemented the explanation.

Comment 2: The first part of Scheme 2, although well know, needs to be better explained.

Response 2: We have added more detailed explanations for Scheme 2.

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript, entitled Synthesis of Novel Thiazoles Based on (+)-Usnic
Acid, describes a series of derivatives containing a thiazole ring with
an amide substituent. This work is a continuation of a previous
publication in New J. Chem. 2023, 47(43), 19865-19879. New compounds
were obtained and fully characterized by spectral methods.
I have a few minor recommendations:
1) In part 3. Materials and Methods, everywhere check and correct the
font. For example in line 101 -
(R)-N-(4-(8-acetyl-1,3,7-trihydroxy-2,9a-dimethyl-9-oxo-9,9a-dihydrodibenzo[b,d]furan-4
-yl)thiazol-2-yl)benzamide should be written as
(R)-N-(4-(8-Acetyl-1,3,7-trihydroxy-2,9a-dimethyl-9-oxo-9,9a
-dihydrodibenzo[b,d]furan-4-yl)thiazol-2-yl)benzamide

2) In several places in the References section, Abbreviated Journal
Names are incorrect. For example, the European Journal of Medicinal
Chemistry should be Eur. J. Med. Chem.

3) HRMS are presented in the Supplementary Material - is that right?

Author Response

Dear Reviewer,  

Thank you for reading our article and for Your helpful comments!

Comment 1: In part 3. Materials and Methods, everywhere check and correct the
font. For example in line 101 -
(R)-N-(4-(8-acetyl-1,3,7-trihydroxy-2,9a-dimethyl-9-oxo-9,9a-dihydrodibenzo[b,d]furan-4
-yl)thiazol-2-yl)benzamide should be written as
(R)-N-(4-(8-Acetyl-1,3,7-trihydroxy-2,9a-dimethyl-9-oxo-9,9a
-dihydrodibenzo[b,d]furan-4-yl)thiazol-2-yl)benzamide

Response 1: We've corrected all the names of the compounds.

Comment 2: In several places in the References section, Abbreviated Journal
Names are incorrect. For example, the European Journal of Medicinal
Chemistry should be Eur. J. Med. Chem.

Response 2: We've checked and corrected all the abbreviations in References section. 

Comment 3: HRMS are presented in the Supplementary Material - is that right?

Response 3: That's not quite correct. Mass spectra of compounds can be found in the supplementary materials. We have corrected this point in the text of the article and supplementary materials.  

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript entitled "Synthesis of novel thiazoles based on (+)-usnic acid" presented by Filimonov, A. et.al., describes the synthesis of a series of usnic acid derivatives containing a thiazole ring with an amide substituent. The manuscript is well organized and written. Problem to obtaining desired thiazole-amides was resolved elegantly avoiding the direct acylation of the thiazole amine with an acid chloride, forming an alternative acyl-thioureas intermediates, followed by cyclization. 

Synthesized compounds were well purified and characterized. Obtained compounds should have a valuable potential as biological active molecules.

Author Response

Dear Reviewer,  
Thank you for reading our article and leaving such a nice review!