74743-62-7Relevant academic research and scientific papers
Studies Related to Thietan-2-ones. Part 2. Conversion of a Benzylpenicillin-derived Thietan-2-one into D- and L-2-Methylpenicillamines
Crilley, Martine M. L.,Stoodley, Richard J.
, p. 1127 - 1132 (2007/10/02)
(3R)- and (3S)-hept-2-en-6-yl>-3,4,4-trimethylthietan-2-ones (8b) and (9b) were isomerised to (3R)- and (3S)-3-(2-benzyloxazol-5-ylcarbonyl)amino-3,4,4-trimethylthietan-2-ones (10) and (14) by m-chlorobenzoic acid in methanol.Attempts to cleave the amide linkage of compound (10), by the action of phosphorus(V) chloride-methanol, were unrewarding.In dichloromethane containing boron trifluoride, compound (8b) was converted into (3R)-3-(2-benzyl-5-oxo-2-oxazolin-4-ylidene)amino-3,4,4-trimethylthietan-2-one (16).Ozonolysis of the lastmentioned compound in dichloromethane at -78 deg C and addition of ethanol yielded (3R)-3-(formyl)amino-3,4,4-trimethylthietan-2-one (17) and N-(ethoxycarbonyl)phenylacetamide (22a).Removal of the formyl group from compound (17) was achieved by the action of phosphorus(V) trichloride oxide-methanol to give, following addition of toluene-p-sulphonic acid, (3R)-3-amino-3,4,4-trimethylthietan-2-one toluene-p-sulphonate (4c).In boiling water, the thietanone (4c) underwent hydrolysis to give (2S)-2-amino-2,3-dimethyl-3-mercaptobutanoic acid toluene-p-sulphonate (D-2-methylpenicillamine toluene-p-sulphonate) (27b).Using a similar reaction sequence, the thietanone (9b) was transformed into L-2-methylpenicillamine toluene-p-sulphonate (28b).D-Penicillamine toluene-p-sulphonate (27a) underwent thiazolidine formation with formaldehyde more rapidly than did compound (27b).
Studies Related to Penicillins. Part 19. Alkylations of (3R)-3-hept-2-en-6-yl>-4,4-dimethylthietan-2-one
Carter, Stephen D.,Kaura, Arun C.,Stoodley, Richard J.
, p. 388 - 394 (2007/10/02)
The title compound (7a) unergoes epimerisation at position 3 of the thietanone ring in the presence of triethylamine; the equilibrium ratio of the starting material and its epimer (9a) is ca. 1.5 : 1.Methylation of the compounds (7a) or (9a) also occurs at position 3 of the thietanone ring, in the presence of sodium hydride-methyl iodide; a ca. 1 : 1 mixture of the (3R)-3-methylthietanone (7b) and the (3S)-3-methylthietanone (9b) is produced when tetrahydrofuran is used as the solvent whereas a ca. 2.5 : 1 mixture of the compounds (7b) and (9b) is formed when NN-dimethylformamide is employed.With potassium t-butoxide-t-butyl bromoacetate in NN-dimethylformamide, the thietanone (7a) affords a ca. 6 : 1 mixture of the (3R)-3-t-butyloxycarbonylmethylthietanone (7c) and its (3S)-isomer (9c).Only the (3R)-3-allylthietanone (7d) is formed when the thietanone (7a) is treated with potassium t-butoxide-allyl iodide in NN-dimethylformamide.Attempts to hydroxymethylate the thietanone (7a), by using potassium t-butoxide-formaldehyde, were thwarted by further reactions of the hydroxymethyl derivative (7e) or (9d), resulting in the formation of a mixture of 7-(α-mercapto-α-methylethyl)-3-phenylacetamido-1-aza-5,9-dioxabicyclodec-2-ene-4,8-dione (16a) and 11,11-dimethyl-5-phenylacetamido-3,9-dioxa-12-thia-7-azatricyclo1,7>dodecane-4,10-dione (20).
