Several years ago considerable interest was aroused by the discovery by van Veen and Hyman (1) of a new naturally occurring sulfur-containing amino acid which they had isolated from the djenkol bean (Pithecolobium lobatum) and named djenkolic acid. They showed that it was probably the cysteine thioacetal of formaldehyde. This structure was confirmed by du Vigneaud and Patterson (2) who synthesi...

Residue-specific bioincorporation of 1,3thiazolidine-4-carboxylic acid [thiaproline, Pro(S)], a nonnatural amino acid analog of proline, into human recombinant annexin V was achieved with a proline-auxotrophic Escherichia coli strain by fermentation procedures in minimal medium. Quantitative replacement of proline with thiaproline was confirmed by mass-spectrometric, amino acid, and x-ray cryst...

1,3-Dipolar cycloaddition of azomethine ylides derived from acenaphthylene-1,2-dione and 5methyl-benzo[b]-thiophene-2,3-dione with L-proline, thiazolidine-4-carboxylic acid and 1,2,3,4tetrahydroisoquinoline-3-carboxylic acid with various electron deficient dipolarophiles leads to the formation of novel spiroheterocycles having two or more chiral centers. Semiempirical studies have been performe...

This work includes synthesis a series of some new derivatives triazine from reaction between the sulfur amino acid (L-cysteine) and different aldehydes in dry ethanol to obtain thiazolidine ring as diastereo isomers (Cis Trans)- 2- alkylthiazolidine-4- carboxylic acids (1).
 The (1) suffered esterfication presence drops concentrated sulfuric catalyst give esters :
 ethyl alkylthiazoli...