Pyrazole derivatives (pyrazolones): phenylbutazone and oxyphenbutazone. Oxicams: piroxicam. COX-2 inhibitors: celecoxib, etodolac, meloxicam, rofecoxib, and valdecoxib.
Table of Contents
Which is the example of pyrazole derivatives?
Pyrazole derivatives (pyrazolones): phenylbutazone and oxyphenbutazone. Oxicams: piroxicam. COX-2 inhibitors: celecoxib, etodolac, meloxicam, rofecoxib, and valdecoxib.
What are the biological potency of pyrazole derivatives?
Pyrazoles are reported to possess a wide range of biological activities in literature such as anti-microbial, anti-fungal, anti-tubercular, anti-inflammatory, anti-convulsant, anticancer, anti-viral, angiotensin converting enzyme (ACE) inhibitory, neuroprotective, cholecystokinin-1 receptor antagonist, and estrogen …
What are imidazole derivatives?
Many imidazole-based derivatives have been marketed as antifungal drugs such as ketoconazole (1), miconazole (2), clotrimazole (3), tioconazole (4), econazole (5), tinidazole (6), enilconazole/imazalil (7), parconazole (8), eberconazole (9), lanoconazole (10), fenticonazole (11), bifonazole (12), sulconazole (13).
Is Oxazole basic?
Oxazole is a weak base; its conjugate acid has a pKa of 0.8, compared to 7 for imidazole.
What is a pyrazole ring?
pyrazole, any of a class of organic compounds of the heterocyclic series characterized by a ring structure composed of three carbon atoms and two nitrogen atoms in adjacent positions. The simplest member of the pyrazole family is pyrazole itself, a compound with molecular formula C3H4N2.
What is difference between imidazole and pyrazole?
The most important structural change between imidazole and pyrazole is in the relative position of two nitrogen atoms. In imidazole nitrogens are separated by one carbon atom, in pyrazole, they are next to each other.
Is pyrazole acidic or basic?
weak base
Pyrazole is a weak base, with pKb 11.5 (pKa of the conjugated acid 2.49 at 25 °C). Pyrazoles are also a class of compounds that have the ring C3N2 with adjacent nitrogen atoms.
How do you make pyrazole?
Pyrazole or isoxazole derivatives are prepared by a palladium-catalyzed four-component coupling of a terminal alkyne, hydrazine (hydroxylamine), carbon monoxide under ambient pressure, and an aryl iodide.
Is metronidazole an imidazole derivative?
Abstract. Metronidazole is a imidazole derivative with antibacterial and antiprotozoal activity. Despite its therapeutic efficacy, several studies have been developing new imidazole derivatives with lower toxicity.
Why imidazole is more basic than pyrazole?
iii) Pyrazole is much weaker base than imidazole and pyridine although it also have two nitrogen atoms as in case of imidazole. This difference is due to the fact that the positive charge in pyarzolium ion is less stabilized than in the imidazolium ion and pyridinium ion.
Is Pyrazine basic?
Pyrazine is a heterocyclic aromatic organic compound with the chemical formula C4H4N2. It is a symmetrical molecule with point group D2h. Pyrazine is less basic than pyridine, pyridazine and pyrimidine. It is a “deliquescent crystal or wax-like solid with a pungent, sweet, corn-like, nutty odour”.
What is pyran ring?
In chemistry, pyran, or oxine, is a six-membered heterocyclic, non-aromatic ring, consisting of five carbon atoms and one oxygen atom and containing two double bonds. The molecular formula is C5H6O. There are two isomers of pyran that differ by the location of the double bonds.
What is a furan ring?
Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen atom. Chemical compounds containing such rings are also referred to as furans. Furan is a colorless, flammable, highly volatile liquid with a boiling point close to room temperature.
Which is more basic pyrrole or pyrazole?
pyrrole (pkb-13.6) : Non basic (or can refer as a very weakly basic in nature). pyrazole (pkb-11.5) : The inductive effect is larger in pyrazole because the two N atoms are closer Hence, the pyrazole is a weaker base compare to imidazole.
Which is more basic pyrazole or imidazole?
Explain why pyrazole is a weaker base than imidazole. Answer: The sp2 orbital of nitrogen is the site of protonation in both pyrazole and imidazole. The nitrogen atom bonded to hydrogen is not basic because its lone pair of electrons is part of the aromatic ring system.