Chemical name (R) -3 – [(S) – (5 – O -2 – pyrrolo alkyl) carbonyl] – thiazolidine -4 – formic acid, is a new synthetic immune enhancers, and its structure similar to the dipeptide. Good oral and intramuscular bioavailability, both for non-specific immune response and contribute to specific immune response ; can promote macrophage and neutrophil phagocytic activity, activation of natural killer cells  ; promote mitotic cell proliferation caused by the source, so that when the change in immunocompromised T cells and helper T cell suppression ratio returned to normal ; by stimulating IL -2 and IFN- promote the cellular immune response [ 4]. Clinical prevention and treatment of children for recurrent respiratory infections (RRI), chronic bronchitis, recurrent urinary tract infection and adjuvant treatment of malignant Cancer Swift progress has been satisfactory results. Its good tolerance, low incidence of adverse reactions. This product is in the late ’80s by the Italian Poli developed chemical industry, and in 1993 the brand name Polimod the first time in Italy is listed as inhibition of tumor cell growth and recurrent episodes of respiratory and urinary tract infection .
We refer to [6 ~ 8] and were modified L-cysteine and L-pyroglutamic acid as the starting material, 3-step reaction by successfully synthesized pidotimod samples. The first step reaction L-thiazolidine -4 – carboxylic acid preparation than  greatly improved  is L-cysteine hydrochloride with formaldehyde, then adding pyridine and ethanol, high cost and serious pollution; and we need only L-cysteine with formaldehyde can, low cost, simple operation and less pollution.
Specific synthesis: 1 L-thiazolidine -4 – carboxylic acid (2)
In 1L beaker, then added to the L-cysteine (60g, 0.38mol), distilled water (240ml) was dissolved by adding 40% formaldehyde solution (34ml, 0.38mol), at room temperature for overnight, Filter Was a colorless needle crystal, crude distilled water (100ml) recrystallization filtration, drying was colorless needle crystal 40g (78%), mp: 196 ~ 197 (decomposition), Rotation: [ ] 20D =- 141 (c2, water) [literature  mp: 196 ~ 197 , [ ] 20D =- 141 (water)].
2 L-pyroglutamic acid ester of pentachlorophenol (3)
1L three neck bottle in order to join L-pyroglutamic acid (51.6g, 0.4mol), pentachlorophenol (105.4g, 0.4mol), dimethylformamide (DMF, 500ml), dicyclohexyl carbodiimide (DCC, 82.6g, 0.4mol), at 5 and stirred 16h, 60 under vacuum distillation the reaction solution to dry, soaked with the appropriate amount of ethyl acetate, filtered crude product was 73g (50%), may used directly for next step reaction. mp: 179 ~ 182 [literature  mp: 180 ~ 184 ].
3 pidotimod (1) 1L 3 neck in the bottle, then added to the L-thiazolidine -4 – carboxylic acid (40g, 0.3mol), triethylamine (30g, 0.3mol), dimethylformamide (500ml), stirred at room temperature 30min, and then joined the PCP L-pyroglutamic acid ester (113g, 0.3mol), at room temperature 24h, filtered, Filtrate 60 under vacuum distillation to dryness, extracted with 500 ml distilled water, aqueous solution with 37% hydrochloric acid (25ml, 0.3mol) acidification, crystallization standing at 10 8h, then filtration crystal 56g, recrystallized with distilled water was fine 50g (69 %), mp: 192 ~ 194 , [ ] 25D =- 150 (c2, 5N HCl) [literature  mp: 192 ~ 194 , [ ] 25D =- 150 (c 2,5 N hydrochloric acid )].
[References]  Pharmacol Res, 1990,22 (Suppl 2) :126-129.
 Arzneim Forsch / Drug Res ,1994,12:1421-1424.
 Arzneim Forsch / Drug Res ,1994,12:1476-1479.
 Int J Immunother, 1992,8 (4) :212-216.
 Drugs Fut, 1994,19 (12) :1133-1134.
 J Am Chem Soc ,1937,59:200-206.
 J Med Chem, 1970,13 (5): 843.
 US 4,839,387 (1989) :13-17.
 Arzneim-Forsch/Drug Res, 1994,44
The e-commerce company in China offers quality products such as Package Tracker , Mini Pet Tracker, and more. For more , please visit Mini Pet Tracker today!
[wpr5-amazon asin=”B078QCRYWJ” region=”com”]