Nitrogen‐, and/or Sulfur-Containing Heterocyclic Rings Poulomi Majumdar,†,‡ Anita Pati,†,§ Manabendra Patra, Rajani Kanta Behera,† and Ajaya Kumar Behera*,† †Organic Synthesis Laboratory, School of Chemistry, Sambalpur University, Jyoti Vihar, Burla 768019, Orissa, India ‡State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, P.R. China School of Applied Sciences (Chemistry), KIIT University, Bhubaneswar 751024, India National Institute of Science & Technology, Palur Hill, Berhampur 761068, Orissa, India

Acid hydrazides, potent reagents for synthesis of oxygen-, nitrogen-, and/or sulfur-containing heterocyclic rings.

2.3. Amides and Lactams 3435 2.4. Imides 3448 2.5. Thiophenes 3451 2.6. Thiazolines, Thiazoles, and Thiazines 3454 2.7. Dithiazoles 3456 2.8. Thiadiazoles 3456 2.9. Imidazolines and Pyrimidines 3456 2.10. Alcohols 3458 2.11. PdO to PdS 3461 2.12. Reduction 3462 2.13. Nucleotides, Purines, and Pyrimidines 3463 2.14. Miscellaneous 3467 2.15. P4S10 vs Lawesson’s Reagent (LR) 3473 3. Conclusion 3473 4. Acknowledgments 3473 5. References 3473

A Berzelius Reagent, Phosphorus Decasulfide (P4S10), in Organic Syntheses

1,3,4-Thiadiazoles: a potent multi targeted pharmacological scaffold.

Ylides at a crossing: An unprecedented 1,3-dipolar cycloaddition (cross-cycloaddition) between two different ylides was realized by using the chiral Cu(I) /tBu-Phosferrox complex as the catalyst under mild reaction conditions. This catalytic system provides an expeditious approach to the construction of highly functionalized 1,2,4-triazinane derivatives in good yields with excellent diastereoselectivities and enantioselectivities.

Catalytic Asymmetric 1,3-Dipolar Cycloaddition of Two Different Ylides: Facile Access to Chiral 1,2,4-Triazinane Frameworks†

Synthesis of some novel pyrazolo[3,4-b]pyridine and pyrazolo[3,4-d]pyrimidine derivatives bearing 5,6-diphenyl-1,2,4-triazine moiety as potential antimicrobial agents.

Pyridazine derivatives and related compounds. Part 13: Synthesis and antimicrobial activity of some pyridazino[3',4':3,4]pyrazolo[5,1-c]-1,2,4-triazines.

The current work concentrates on generating different topologies by using the\n concept of the ideal. These topologies are used to make more thorough\n studies on generalized rough set theory. The rough set theory was first\n proposed by Pawlak in 1982. Its core concept is upper and lower\n approximations. The principal goal of the rough set theory is reducing the\n vagueness of a concept to uncertainty areas at their borders by increasing\n the lower approximation and decreasing the upper approximation. For the\n mentioned goal, different methods based on ideals are proposed to achieve\n this aim. These methods are more accurate than the previous methods. Hence\n it is very interesting in rough set context for removing the vagueness\n (uncertainty).

/pdf/idealization-of-j-approximation-spaces-2cu6xvcx2y.pdf

Idealization of j-approximation spaces

The reaction of the hydrazide of pyridazino[3′, 4′:3, 4]pyrazolo[5, 1-c]-1,2,4-triazine-3-carboxylic acid 3 with carbon disulfide in the presence of potassium hydroxide gave the 1,3,4-oxadiazole-2-thione derivative 4. The methylation of this product in an alkaline medium proceeds at the sulfur atom. The reaction of 3 with KOH and carbon disulfide followed by addition of hydrazine hydrate afforded the 4-amino-1,2,4-triazole derivative 6. Compound 3, when heated either with ammonium thiocyanate or with potassium thiocyanate, afforded the same product 7, which underwent cyclodehydration in the presence of acetyl chloride, which led to the 2-acetylamino-1,3,4-thiadiazole derivative 8. In a basic medium, the product was 1,2,4-triazole-3-thione derivative 9. The reaction of 3 with phenyl isothiocyanate provided thiosemicarbazide derivative 10, which underwent cyclodehydration in a basic medium and gave the 1,2,4-triazole derivative 11. The reaction of 3 with formic acid yielded the 3-carboxyl-2′-(formyl)hydrazi...

Pyridazine Derivatives and Related Compounds, Part 17: 1 The Synthesis of Some 3-Substituted Pyridazino[3′, 4′:3, 4]pyrazolo[5, 1-c]-1,2,4-triazines and Their Antimicrobial Activity

On generalization of rough sets by using two different methods

The original model of rough sets was advanced by Pawlak, which was mainly involved with the approximation of things using an equivalence relation on the universal set of his approximation space. In this paper, two kinds of approximation operators via ideals which represent extensions of Pawlak’s approximation operator have been presented. In both kinds, the definitions of upper and lower approximations based on ideals have been given. Moreover, a new type of approximation spaces via two ideals which is called bi-ideal approximation spaces was introduced for the first time. This type of approximations was analyzed by two different methods, their properties are investigated, and the relationship between these methods is proposed. The importance of these methods was its dependent on ideals which were topological tools, and the two ideals represent two opinions instead of one opinion. At the end of the paper, an applied example had been introduced in the chemistry field by applying the current methods to illustrate the definitions in a friendly way.

Mona Hosny

Papers

Pyridazine derivatives and related compounds. Part 13: Synthesis and antimicrobial activity of some pyridazino[3',4':3,4]pyrazolo[5,1-c]-1,2,4-triazines.

Idealization of j-approximation spaces

Pyridazine Derivatives and Related Compounds, Part 17: 1 The Synthesis of Some 3-Substituted Pyridazino[3′, 4′:3, 4]pyrazolo[5, 1-c]-1,2,4-triazines and Their Antimicrobial Activity

On generalization of rough sets by using two different methods

Bi-ideal approximation spaces and their applications