[1,2,5]Thiadiazolo[3,4-b]pyrazine-5,6(4H,7H)-dione

Round 1

Reviewer 1 Report

This manuscript refers to the synthesis of [1,2,5]thiadiazolo[3,4-b]pyrazine-5,6(4H,7H)-dione. In Ref. 11, this compound was prepared by condensation reaction of oxalic acid and diaminothiadiazole with hydrochloric acid as a catalyst when synthesizing 5,6-dichloro-[1,2,5]thiadiazolo[3,4-b]pyrazine, but it was not isolated and was derived to 5,6-dichloro-[1,2,5]thiadiazolo[3,4-b]pyrazine. Therefore, no spectral data is reported. Therefore, I recommend the publication of this manuscript, including the synthesis method and spectral data, in Molbalk, but the authors need to explain the following points and revise the manuscript.

1. The authors have described the structural formula of compound 1 as a keto-keto form. Structurally, enol-enol and enol-keto forms also exist. The NMR spectra indicate that it exists in either the keto-keto form or the enol-enol form. A comment is needed explaining why it is the keto-keto form.
2. Line 32 states the name of compound 1. The name of compound 1 appears multiple times in subsequent lines, making the statement redundant.

Author Response

Reviewer 1

The authors are grateful to the reviewer for a kind and highly professional review.

Point 1.

The authors have described the structural formula of compound 1 as a keto-keto form. Structurally, enol-enol and enol-keto forms also exist. The NMR spectra indicate that it exists in either the keto-keto form or the enol-enol form. A comment is needed explaining why it is the keto-keto form.

Response from authors.

Unfortunately, there are no studies on the fine structure of such compounds in the literature, and we also have no data indicating the existence of enol or keto forms. In this paper, as in most works on similar structures, we preferred to write the most probable, in our opinion, structure with two amide fragments.

Point 2.

Line 32 states the name of compound 1. The name of compound 1 appears multiple times in subsequent lines, making the statement redundant.

Response from authors.

In accordance with the reviewer's recommendations, the name of compound 1 is referred to in an abbreviated form in most cases.