3581-91-7

Basic information

• Product Name: 4,5-Dimethylthiazole
• Synonyms: FEMA NUMBER 3274;FEMA 3274;4,5-DIMETHYL-1,3-THIAZOLE;4,5-DIMETHYLTHIAZOLE;4,5-dimethyl-thiazol;4 5-DIMETHYLTHIAZOLE 97+%;4,5-Dimethylthiazole,98%;dimethylthiazole,4,5-dimethylthiazole
• CAS NO: 3581-91-7
• Molecular Formula: C₅H₇NS
• Molecular Weight: 113.18
• EINECS: 222-703-3
• Product Categories: Heterocyclic Compounds;Thiazoles;thiazole Flavor;Alphabetical Listings;C-D;Flavors and Fragrances;Building Blocks;Heterocyclic Building Blocks
• Mol File: 3581-91-7.mol
• Article Data: 11

Chemical Properties

• Melting Point: 83-84 C
• Boiling Point: 158 °C742 mm Hg(lit.)
• Flash Point: 124 °F
• Appearance: /solid
• Density: 1.07 g/mL at 25 °C(lit.)
• Vapor Pressure: 3.46mmHg at 25°C
• Refractive Index: n20/D 1.521(lit.)
• Storage Temp.: Sealed in dry,Room Temperature
• PKA: pK1:3.73 (25°C,μ=0.1)
• BRN: 105694
• CAS DataBase Reference: 4,5-Dimethylthiazole(CAS DataBase Reference)
• NIST Chemistry Reference: 4,5-Dimethylthiazole(3581-91-7)
• EPA Substance Registry System: 4,5-Dimethylthiazole(3581-91-7)

Safety Data

• Hazard Codes: Xn,Xi,F
• Statements: 10-22-37/38-41-36/37/38
• Safety Statements: 16-26-39-37/39-36/37/39
• RIDADR: UN 1993 3/PG 3
• WGK Germany: 3
• RTECS: XJ4380000
• HazardClass: 3
• PackingGroup: III
• Hazardous Substances Data: 3581-91-7(Hazardous Substances Data)

Usage

Chemical Properties

4,5-Dimethylthiazole is a colorless to light yellow liquid that has a roasted nutty, meaty, boiled poultry-like odor.

Occurrence

Reported found in peanuts, toasted oats, malt, peach, pork, coffee, krill, shrimp and scallops

Uses

4,5-Dimethylthiazole was used in the preparation of 4-(bromomethyl)-5-(dibromomethyl)thiazole.

Preparation

From methyl-α-bromoethyl ketone; by oxidation of 2-mercaptothiazoles with hydrogen peroxide in aqueous solution; from 2-mercapto-4,5-dimethylthiazole.

Aroma threshold values

Detection: 470 ppb

Taste threshold values

Taste characteristics at 5 ppm: fishy, amine and pyridine-like with shrimp and savory nuances

Synthesis Reference(s)

The Journal of Organic Chemistry, 6, p. 764, 1941 DOI: 10.1021/jo01205a011

General Description

4,5-Dimethylthiazole is a thiazoles compounds that containing a thiazole ring substituted at positions 4 and 5 only. Radical bromination of 4,5-dimethylthiazole using N-bromosuccinimide in the presence of 2,2′-azobisisobutyronitrile yields mono-, tri- and tetrabromo compounds.

InChI:InChI=1/C5H7NS/c1-4-5(2)7-3-6-4/h3H,1-2H3

Upstream product

• 128608-50-4 2-hydrazino-4,5-dimethyl-thiazole; hydrochloride 
• 77287-34-4 formamide 
• 814-75-5 3-bromo-butanone 
• 21709-64-8 3-formylamino-butan-2-one 
• 134657-89-9 trichloro(4,5-dimethylthiazole)gold(III) 
• 52-90-4 L-Cysteine 
• 50-81-7 ascorbic acid 
• 178101-88-7 [1-¹³C]ascorbic acid 
• 16887-00-6 chloride 
• 79247-96-4 4,5-dimethyl-thiazole-2-carboxylic acid ethyl ester 
• 19322-27-1 4-hydroxy-5-methyl-3[2H]-furanone 
• 4091-39-8 3-chloro-2-butanone 
• 2289-75-0 4,5-dimethyl-1,3-thiazole-2-amine 
• 3332-09-0 N-methylimine of methyl ethyl ketone 

Downstream Products

• 7531-76-2 1-(4,5-dimethylthiazol-2-yl)ethanone 
• 15055-59-1 2-benzyl-4,5-dimethyl-thiazole 
• 28168-48-1 (4,5-dimethylthiazol-2-yl)(phenyl)methanone 
• 99839-16-4 (4,5-dimethyl-1,3-thiazol-2-yl)methanol 
• 533885-39-1 2-methoxymethyl-4,5-dimethyl-thiazole 
• 103503-10-2 4,5-dimethyl-2-(4-nitro-phenyl)-thiazole 
• 100192-04-9 2-(4-methoxyphenyl)-4,5-dimethylthiazole 
• 28168-49-2 (4-chloro-phenyl)-(4,5-dimethyl-thiazol-2-yl)-methanone 
• 169899-58-5 2-(1-hydroxy-1-phenylmethyl)-4,5-dimethylthiazole 
• 16206-89-6 3-benzyl-4,5-dimethylthiazol-3-ium chloride 
• 82294-70-0 4-methyl-1,3-thiazole-5-carbaldehyde 
• 181070-74-6 3-Amino-4,5-dimethylthiazolium mesitylenesulfonate 
• 1208121-55-4 5,6-dimethoxycarbonyl-2,3-dimethyl-8-formyl-7-(2'-hydroxy-5'-methyl-benzoyl)-5H-[1,3]thiazolo[3,2-a]pyridine 
• 1208121-56-5 5,6-dimethoxycarbonyl-2,3-dimethyl-8-formyl-7-(2'-hydroxy-5'-isopropylbenzoyl)-5H-[1,3]thiazolo[3,2-a]pyridine 

Relevant articles and documents

Mechanism of formation of sulphur aroma compounds from l-ascorbic acid and l-cysteine during the Maillard reaction

The sulphur aroma compounds produced from a phosphate-buffered solution (pH 8) of l-cysteine and l-, l-[1-13C] or l-[4-13C] ascorbic acid, heated at 140 ± 2 °C for 2 h, were examined by headspace SPME in combination with GC-MS. MS data indicated that C-1 of l-ascorbic acid was not involved in the formation of sulphur aroma compounds. The sulphur aroma compounds formed by reaction of l-ascorbic acid with l-cysteine mainly contained thiophenes, thiazoles and sulphur-containing alicyclic compounds. Among these compounds, 1-butanethiol, diethyl disulphide, 5-ethyl-2-methylthiazole, cis and trans-3,5-dimethyl-1,2,4-trithiolane, thieno[2,3-b]thiophene, thieno[3,2-b]thiophene, cis and trans-3,5-diethyl-1,2,4-trithiolane, 1,2,5,6-tetrathiocane, 2-ethylthieno[2,3-b]thiophene, 2,4,6-trimethyl-1,3,5- trithiane and cyclic octaatomic sulphur (S8) were formed solely by l-cysteine degradation, and the rest by reaction of l-ascorbic acid degradation products, such as hydroxybutanedione, butanedione, acetaldehyde, acetol, pyruvaldehyde and formaldehyde with l-cysteine or its degradation products, such as H2S and NH3. A new reaction pathway from l-ascorbic acid via its degradation products was proposed.

Thiazole, imidazole and oxazole compounds and treatments of disorders associated with protein aging

Provided are, among other things, compounds of formula I or IA, . Also provided are methods of treatment with such compounds.

Heterocyclic volatiles formed by heating cysteine or hydrogen sulfide with 4-hydroxy-5-methyl-3(2H)-furanone at pH 6.5

The reaction of 4-hydroxy-5-methyl-3(2H)-furanone (HMF) with cysteine or hydrogen sulfide at pH 6.5 for 60 min at 140°C produced complex mixtures of volatile compounds, the majority of these containing either sulfur or nitrogen. Of the 68 compounds detect