34258-79-2

Basic information

• Product Name: (3Z)-3-[hydroxy(phenylamino)methylidene]-2-methyl-2,3-dihydro-4H-1,2-benzothiazin-4-one 1,1-dioxide
• CAS NO: 34258-79-2
• Molecular Formula: C₁₆H₁₄N₂O₄S
• Molecular Weight: 330.3584
• Mol File: 34258-79-2.mol
• Article Data: 3

Chemical Properties

• Boiling Point: 490.5°C at 760 mmHg
• Flash Point: 250.5°C
• Density: 1.497g/cm³
• Vapor Pressure: 1.94E-10mmHg at 25°C
• Refractive Index: 1.701
• CAS DataBase Reference: (3Z)-3-[hydroxy(phenylamino)methylidene]-2-methyl-2,3-dihydro-4H-1,2-benzothiazin-4-one 1,1-dioxide(CAS DataBase Reference)
• NIST Chemistry Reference: (3Z)-3-[hydroxy(phenylamino)methylidene]-2-methyl-2,3-dihydro-4H-1,2-benzothiazin-4-one 1,1-dioxide(34258-79-2)
• EPA Substance Registry System: (3Z)-3-[hydroxy(phenylamino)methylidene]-2-methyl-2,3-dihydro-4H-1,2-benzothiazin-4-one 1,1-dioxide(34258-79-2)

Safety Data

• Hazardous Substances Data: 34258-79-2(Hazardous Substances Data)

Upstream product

• 35511-15-0 methyl 2-methyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide 
• 62-53-3 aniline 
• 24683-26-9 ethyl 4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide 
• 81-07-2 saccharin 
• 35511-14-9 methyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide 
• 6639-62-9 methyl 3-oxo-2,3-dihydrobenzo[d][1,2]thiazol-2-acetate 1,1-dioxide 
• 24683-21-4 4-hydroxy-2H-1,2-benzothiazine-3-carboxylic acid ethyl ester 1,1-dioxide 
• 128-44-9 saccharin sodium salt 
• 24683-20-3 ethyl 2-(1,1-dioxido-3-oxobenzo[d]isothiazol-2(3H)-yl) acetate 

Downstream Products

• 36798-96-6 4-acetoxy-2-methyl-1,1-dioxo-1,2-dihydro-1λ⁶-benzo[e][1,2]thiazine-3-carboxylic acid anilide 
• 40713-44-8 5-methyl-6,6-dioxo-3-phenyl-5,6-dihydro-6λ⁶-benzo[5,6][1,2]thiazino[3,4-e][1,3]oxazine-2,4-dione 
• 40713-38-0 4-isopropoxy-2-methyl-1,1-dioxo-1,2-dihydro-1λ⁶-benzo[e][1,2]thiazine-3-carboxylic acid anilide 
• 40713-37-9 2-methyl-1,1-dioxo-4-propoxy-1,2-dihydro-1λ⁶-benzo[e][1,2]thiazine-3-carboxylic acid anilide 
• 40713-43-7 4-acetoxy-2-methyl-1,1-dioxo-1,2-dihydro-1λ⁶-benzo[e][1,2]thiazine-3-carboxylic acid N-acetyl-anilide 

Relevant articles and documents

Site-specific acid-base properties of tenoxicam

The Hammett approach, as a new deductive tool, was introduced to characterize the otherwise inaccessible minor protonation pathway of tenoxicam (1), the non-steroidal anti-inflammatory drug. A total of eight compounds, constituting a systematic series of side chain-substituted analogues of tenoxicam and piroxicam (2), were synthesized and studied in terms of acid-base properties and Hammett constants to identify the ideal replacement of the unprotonated pyridin-2-yl group, a key moiety in both molecules. Hammett constants of the phenyl substituents have been found to be in a linear correlation with the experimental log K values of the enolate sites, the basic moiety of the extended conjugated system in this family of piroxicam derivatives. Then, a similar correlation was observed for the analogous tenoxicam derivatives. After identifying the 2-aza Hammett constant of the pyridin-2-yl group and the corresponding log K value, the site-specific acid-base properties of tenoxicam could be quantitated. This novel method is assessed to be a fine-tuning tool to find the ideal substituent by using analogue-based deductive method to obtain site-specific constants of the minor protonation/deprotonation pathway in drugs and biomolecules. The tenoxicam microconstant values indicate that the enolate moiety is of extremely low basicity (reflected by the log kO = 3.70 and log kO N = 1.09 values), which can, however, be interpreted in terms of the peculiar ring system and the overwhelming electron-withdrawing effects of the adjacent heteroatoms. A diagram depicting the pH-dependent distribution of 1 microspecies is also presented.

Synthesis and antiinflammatory activity of some 3-carboxamides of 2-alkyl-4-hydroxy-2H-1,2-benzothiazine 1,1-dioxide.

-