Synthetic Library of Oligosaccharides Derived from the Capsular Polysaccharide of Serotypes 6A and 6B and Their Immunological Studies.

serotypes 6A and 6B are two of the common causes of invasive pneumococcal diseases. Although capsular polysaccharide conjugates of these two serotypes are included in the leading 13-valent pneumococcal conjugate vaccine, its low immunogenicity and high threshold for manufacturing technology indicated the need for vaccine improvement. Structurally defined synthetic immunogens have potential in dealing with these problems.

A Synthetic Carbohydrate-Protein Conjugate Vaccine Candidate against Serotype K2.

causes pneumonia and liver abscesses in humans worldwide and contains virulence factor capsular polysaccharides and lipopolysaccharides linked to the cell wall. Although capsular polysaccharides are good antigens for vaccine production and capsular oligosaccharides conjugate vaccines are proven effective against infections caused by encapsulated pathogens, there is still no vaccine available. One obstacle is that the capsular polysaccharide of a dominated serotype K2 is difficult to synthesize chemically due to the three 1,2- linkages in its structure.

Synthesis of Asymmetric -Glycans as Common Core Substrates for Structural Diversification through Selective Enzymatic Glycosylation.

-glycans on the cell surface provide distinct signatures that are recognized by different glycan-binding proteins (GBPs) and pathogens. Most glycans in humans are asymmetric and isomeric, yet their biological functions are not well understood due to their lack of availability for studies. In this work, we have developed an improved strategy for asymmetric -glycan assembly and diversification using designed common core substrates prepared chemically for selective enzymatic fucosylation and sialylation.

Synthetic carbohydrate-based vaccines: challenges and opportunities.

Glycoconjugate vaccines based on bacterial capsular polysaccharides (CPS) have been extremely successful in preventing bacterial infections. The glycan antigens for the preparation of CPS based glycoconjugate vaccines are mainly obtained from bacterial fermentation, the quality and length of glycans are always inconsistent. Such kind of situation make the CMC of glycoconjugate vaccines are difficult to well control.

Synthesis, antitubercular and anticancer activity of new Baylis-Hillman adduct-derived -cinnamyl-substituted isatin derivatives.

Baylis-Hillman adduct-derived -cinnamyl-substituted isatin derivatives were synthesized and evaluated for their antitubercular activity on HRv strain ATCC 27294 by agar dilution method. Anticancer activity for the same compounds was also screened on four different cell lines: Chinese hamster ovary (CHO cells), Colo 205 (human colon cancer), Sup-T1 (human lymphoma) and C6 glioma (rat glioma) by MTT assay method. The compounds (-) have shown significant activity against strain and the compound has shown specific cytotoxic activity.

Synthesis and biological evaluation of new epalrestat analogues as aldose reductase inhibitors (ARIs).

Baylis-Hillman chemistry derived four series of new epalrestat analogues were synthesized. Three structural changes are introduced in these 39 new epalrestat analogues synthesized. All compounds were evaluated for their in vitro aldose reductase inhibitory (ALR) activity.

Synthesis and evaluation of novel 2-pyridone derivatives as inhibitors of phosphodiesterase3 (PDE3): a target for heart failure and platelet aggregation.

Twenty-six 2-pyridone derivatives (8a-8z), which are structurally analogous to amrinone and milrinone two important cardiotonic drugs, are synthesized and characterized. The synthesis of 2-pyridone derivatives involves addition, followed by cyclization between Baylis-Hillman acetates (7a-7k) and enamino esters or nitriles (3a-3e). Thus synthesized pyridones were subjected to PDE3 inhibitory activity, 14 pyridones were found to be hits out of 26 pyridones synthesized and out of 14 hits, there are 5 pyridones found to be lead compounds having excellent PDE3 inhibitory activity.

Photochemical dehydrogenation of 3,4-dihydro-2-pyridones.

Photochemical dehydrogenation of various substituted 3,4-dihydro-2-pyridones was achieved in a very efficient way by employing 10-15 mol% of photo-induced electron transfer sensitizers like 9-cyanoanthracene, 9-cyanophenanthrene and 1-cyanonaphthalene in presence of molecular oxygen, for the first time.