Skip to main content



Clinical courses


Clinical courses

Chaitanya Prasad Meher
Assistant professor,
Department of pharmaceutical chemistry,
Vijaya Institute Of Pharmaceutical Sciences For Women,
Enikepadu, Vijayawada (A.P)

The chemistry of heterocyclic compounds is a vast subject. Heterocyclic chemistry is an underpinning science for a whole host of areas that are vital for mankind’s future. One of the leading heterocyclic compound is the thiazole. Thiazole and their derivatives are found in certain natural products, viz.vitamin B1 (thiamine) and penicillins. Sulphathiazole (a member of sulpha drugs) is also a derivative of thiazole. The important physiological properties of these compound have stimulated interested in thiazole chemistry.


A heterocyclic compound is an organic compound in which one or more of the carbon atoms in the backbone of the molecule has been replaced by an atom other than carbon. Typical hetero atoms include nitrogen, oxygen, and sulfur. Heterocyclic compounds play very important role in life processes. Both synthetic and natural heterocyclic compounds are the subject of R&D units of many pharmacological and agrochemical and industrial laboratories. Approximately 90% of new drugs contain heterocyclic moieties.  Synthetic heterocycles have wide spread therapeutic uses such as antibacterial, antifungal, antimicrobial, trypanocidal, anti HIV activity, genotoxic, antitubercular, antimalarial, herbicidal, analgesic, anti-inflammatory, muscle relaxant, anticancer agents, hypnotics, sedatives, antidepressant, antimalarial, anthelmentic, antiulcer, insecticidal..etc.,(actually the uses are many and difficult to record.)  With such a great importance, research in heterocyclic chemistry is part of many academic and industrial laboratories worldwide. Out of all the heterocyclic compound thiazole is one of the important area of research because of the manifold pharmacological activities.

Thiazole, or 1,3-thiazole, is a heterocyclic compound that contains both sulfur and nitrogen; the term 'thiazole' also refers to a large family of derivatives. Thiazole itself is a pale yellow liquid with a pyridine-like odor and the molecular formula C3H3NS. The thiazole ring is notable as a component of the vitamin thiamine(B1).

Thiazole is aromatic on the basis of delocalization of a lone pair of electrons from the sulfur atom completing the needed 6 π electrons to satisfy Huckel’s rule. The resonance forms are:

Thiazole is a clear to pale yellow liquid with a boiling point of 116-118oC. Its specific gravity is 1.2 and it is sparingly soluble in water. It is soluble in alcohol and ether. The odor of thiazole is similar to pyridine. It is used as an intermediate to manufacture synthetic drugs, fungicides, and dyes.Its ring structure is also a useful element in medicinal chemistry. This structure has found application in drug development for treatment of allergies, hypertension, inflammation, schizophrenia, and bacterial and HIV infections. Microwave spectra reveal the bond lengths and bond angles in the thiazole molecule. Notice that the C-S bonds are longer than the others because of the larger sulfur atom radius. The bond angles are also influenced by the presence of heteroatoms. The C-S-C angle is comparable to that of thiophene (~ 90o).

1H NMR spectral data shows the following chemical shifts: H-2 8.88 ppm, H-4 7.98 ppm, and H-5 7.41 ppm. The downfield values are typical of aromatic hydrogens. The further downfield shift for H-2 compared to the other hydrogens is due to the deshielding caused by the combined electron-withdrawing effects of nitrogen and sulfur being adjacent to it. 13C NMR spectral data reveals three peaks: C-2 153.4 ppm, C-4 143.7 ppm, and C-5 119.7 ppm, all values typical for aromatic carbons.Important IR bands include a typical C-H stretching mode at 3084 cm-1,ring stretching modes at 1481 cm-1, 1381 cm-1, and 1319 cm-1, and CH modes at 882 cm-1, 865 cm-1, 803 cm-1, and 728 cm-1.

Pharmacological uses of important thiazole derivatives

The heterocyclic compounds are used as chemical intermediates and solvents in the pharmaceutical, chemical, textile, dye-stuffs, petroleum and photography industries. Several compounds also function as vulcanization accelerators in the rubber industry.Compounds classified as heterocyclic probably constitute the largest and most varied family of organic compounds. After all, every carbocyclic compound, regardless of structure and functionality, may in principle be converted into a collection of heterocyclic analogs by replacing one or more of the ring carbon atoms with a different element. Even if we restrict our consideration to oxygen, nitrogen and sulfur (the most common heterocyclic elements), the permutations and combinations of such a replacement are numerous. These include new therapeutic agents, improved molecules to help sustain and enhance food production as well as dyes and electronic molecules that will play an important role in the conservation of energy as well as the next generation of consumer electronics.

1.Ginter-Hanselmayer, Gabriele (March 2009), Arbeitsunterlagenzur 42. WissenschaftlichenFortbildungsveranstaltungfürApothekerinnen und Apotheker: Infektionskrankheiten, ÖsterreichischeApothekerkammer, p. 103
2.Matsueda K, Hongo M, Tack J, Aoki H, Saito Y, Kato H (January 2010). "Clinical trial: dose-dependent therapeutic efficacy of acotiamide hydrochloride (Z-338) in patients with functional dyspepsia - 100 mg t.i.d. is an optimal dosage". Neurogastroenterology and Motility : the Official Journal of the European Gastrointestinal Motility Society22 (6): 618–e173.
3.Bakris GL, Bank AJ, Kass DA, Neutel JM, Preston RA, Oparil S (2004). "Advanced glycation end-product cross-link breakers. A novel approach to cardiovascular pathologies related to the aging process". American Journal of Hypertension17 (12 Pt 2): 23S–30S.
4.Gallardo-Godoy A; Gever J, Fife KL, Silber BM, Prusiner SB, Renslo AR. (2011 Feb 24). "2-Aminothiazoles as therapeutic leads for prion diseases.".J Med Chem54 (4): 1010–21
5.Worlock A. Barbiturate poisoning treated with amiphenazole and bemegride. British Medical Journal. 1956 Nov 10;2(5001):1099-101.
6.Hazen R, Harvey R, Ferris R, et al. (September 2007). "In vitro antiviral activity of the novel, tyrosyl-based human immunodeficiency virus (HIV) type 1 protease inhibitor brecanavir (GW640385) in combination with other antiretrovirals and against a panel of protease inhibitor-resistant HIV". Antimicrob.Agents Chemother.51 (9): 3147–54
7.McNulty, C. A.; Garden, G. M.; Ashby, J.; Wise, R. (1985). "Pharmacokinetics and tissue penetration of carumonam, a new synthetic monobactam".Antimicrobial agents and chemotherapy28 (3): 425–427.
8.Yahav D, Paul M, Fraser A, Sarid N, Leibovici L (2007). "Efficacy and safety of cefepime: a systematic review and meta-analysis". Lancet Infect Dis7 (5): 338–48
9.Essential of pharmacology,K.D.Tripathy,6th edition,p-706
10.Tsuji M, Ishii Y, Ohno A, Miyazaki S, Yamaguchi K (November 1995). "In vitro and in vivo antibacterial activities of S-1090, a new oral cephalosporin".Antimicrob Agents Chemother39 (11): 2544–51.
11.Yokota N, Koguchi M, Suzuki Y, Fukayama S, Ishihara R, Deguchi K, Oda S, Tanaka S, Nakane Y, Fukumoto T (1995). "Antibacterial activities of cefmenoxime against recent fresh clinical isolates from patients in sinusitis".Jpn J Antibiot48 (5): 602–9.
12.BrittaKasten und Ralf Reski (1997): β-lactam antibiotics inhibit chloroplast division in a moss (Physcomitrella patens) but not in tomato (Lycopersiconesculentum). Journal of Plant Physiology 150, 137-140
13.Kolben M, Mandoki E, Ulm K, Freitag K (2001). "Randomized trial of cefotiam prophylaxis in the prevention of postoperative infectious morbidity after elective cesarean section.".Eur J ClinMicrobiol Infect Dis20 (1): 40–2
14.Phillips I, Shannon K (1993). "Importance of beta-lactamase induction".Eur J ClinMicrobiol Infect Dis12 Suppl 1: S19–26
15.Kanafani ZA, Corey GR (February 2009). "Ceftaroline: a cephalosporin with expanded Gram-positive activity". Future Microbiology4: 25–33.
16.White NJ (2003). "Melioidosis".Lancet361 (9370): 1715–722.
17.Gladwin, Mark (2007). Clinical Microbiology Made Ridiculously Simple 4th ed.. Miami, FL: MedMaster, Inc..pp. 67.
18.Reilly, T. M. (1976). "Physiological dependence on, and symptoms of withdrawal from, chlormethiazole". The British Journal of Psychiatry128: 375–378.
19.R Elion, J Gathe, B Rashbaum, and others. The Single-Tablet Regimen of Elvitegravir/Cobicistat/Emtricitabine/TenofovirDisoproxilFumarate (EVG/COBI/FTC/TDF; Quad) Maintains a High Rate of Virologic Suppression, and Cobicistat (COBI) is an Effective Pharmacoenhancer Through 48 Weeks. 50th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC 2010). Boston, September 12–15, 2010.
20.Das J et al. (2006). "2-aminothiazole as a novel kinase inhibitor template. Structure-activity relationship studies toward the discovery of N-(2-chloro-6-methylphenyl)-2-[[6-[4-(2-hydroxyethyl)-1- piperazinyl)]-2-methyl-4-pyrimidinyl]amino)]-1,3-thiazole-5-carboxamide (dasatinib, BMS-354825) as a potent pan-Src kinase inhibitor". J Med Chem49 (23): 6819–32.
21.Robinson, Richard (2010). "New Als Drug Shows Dose-Dependent Efficacy in Phase 2 Trial". Neurology Today10 (13): 1.
22.Romero, G. (August 2006). "Efficacy of selective 5-HT6 receptor ligands determined by monitoring 5-HT6 receptor-mediated cAMP signaling pathways".British Journal of Pharmacology148 (8): 1133–43.
23.Humphries TJ, Merritt GJ (August 1999). "Review article: drug interactions with agents used to treat acid-related diseases". Aliment.Pharmacol.Ther.13 Suppl 3: 18–26
24.Stamp LK, O'Donnell JL, Chapman PT (2007). "Emerging therapies in the long-term management of hyperuricaemia and gout".Internal medicine journal37 (4): 258–66.
25.Brown, K.; Cater, D. P.; Cavalla, J. F.; Green, D.; Newberry, R. A.; Wilson, A. B. (1974). "Nonsteroidalantiinflammatory agents. 1. 2,4-Diphenylthiazole-5-acetic acid and related compounds". Journal of Medicinal Chemistry17 (11): 1177–1181
26.Lee FY, Borzilleri R, Fairchild CR, et al (December 2008). "Preclinical discovery of ixabepilone, a highly active antineoplastic agent".Cancer Chemother.Pharmacol.63 (1): 157–66.
27.Noble, S; Balfour, JA (Mar 1996). "Meloxicam".Drugs51 (3): 424–30; discussion 431–32
28.Gras, J (2012). "Mirabegron for the treatment of overactive bladder".Drugs of today (Barcelona, Spain : 1998)48 (1): 25–32.
29.Atmaca M, Kuloglu M, Tezcan E, Ustundag B, Kilic N (January 2004). "Nizatidine for the treatment of patients with quetiapine-induced weight gain".Hum Psychopharmacol19 (1): 37–40.
30.Ireland, C.; Durso, A.; Newman, R.; Hacker, D. (1982). "Antineoplastic cyclic peptides from the marine tunicate Lissoclinum patella".J. Org. Chem.47 (10): 1807–1811.
31.DeBattista C, Solvason HB, Breen JA, Schatzberg AF. (2000). "Pramipexole augmentation of a selective serotonin reuptake inhibitor in the treatment of depression.".J ClinPsychopharmacol.20 (2): 274–275.
32.Pasqualotto AC, Thiele KO, Goldani LZ (2010). "Novel triazole antifungal drugs: focus on isavuconazole, ravuconazole and albaconazole". CurrOpinInvestig Drugs11 (2): 165–74.
33.Bauer J, et al. (2004). "Ritonavir: An Extraordinary Example of Conformational Polymorphism". Pharmaceutical Research18 (6): 859–866.
34.Lin, TI; Lenz, O; Fanning, G; Verbinnen, T; Delouvroy, F; Scholliers, A; Vermeiren, K; Rosenquist, A et al. (2009). "In vitro activity and preclinical profile of TMC435350, a potent hepatitis C virus protease inhibitor". Antimicrobial agents and chemotherapy53 (4): 1377–85
35.Kitamura Y, Kosaka T, Kakimura JI, et al. (December 1998). "Protective effects of the antiparkinsonian drugs talipexole and pramipexole against 1-methyl-4-phenylpyridinium-induced apoptotic death in human neuroblastoma SH-SY5Y cells".Mol. Pharmacol.54 (6): 1046–54
36.Strosberg AM. (1976). "The cardiovascular pharmacology and hemodynamic activity of tazolol, a selective myocardial beta-stimulant".Arch IntPharmacodynTher.222 (2): 200-15.
37.Bettendorff L, Wirtzfeld B, Makarchikov AF, Mazzucchelli G, Frédérich M, Gigliobianco T, Gangolf M, De Pauw E, Angenot L and Wins P (2007). "Discovery of a natural thiamine adenine nucleotide".Nature Chem. Biol.3 (4): 211–212.
38.Upadhyay MP, West EP, Sharma AP (January 1980). "Keratitis due to Aspergillusflavus successfully treated with thiabendazole". Br J Ophthalmol64 (1): 30–2.
39.Popsavin M, Torovi? L, Svircev M et al. (2006). "Synthesis and antiproliferative activity of two new tiazofurin analogues with 2'-amido functionalities".Bioorg. Med. Chem. Lett.16 (10): 2773–6
40.Fuchs PC, Jones RN, Barry AL (March 1988). "In vitro antimicrobial activity of tigemonam, a new orally administered monobactam". Antimicrob.Agents Chemother.32 (3): 346–9



Subscribe to Pharmatutor Alerts by Email