Building Blocks

4,4'-Dihydroxy-2,2'-bipyridine is a metallo-organic compound that can be used as a homogeneous catalyst for the oxidation of hydroxyl groups. It is also used in cancer research because it has been shown to inhibit tumor cell proliferation and induce apoptosis. 4,4'-Dihydroxy-2,2'-bipyridine is an activated form of 2,2'-bipyridyl with a hydroxyl group on its ortho position. It can be prepared by reacting bromine with the metal salt of 2-hydroxybenzaldehyde in the presence of sodium hydroxide. This reaction produces two products: 4,4'-dihydroxy-2,2'-bipyridine and 2-bromoethanol. The deuterium isotope is used for nuclear magnetic resonance spectroscopy studies because it has a spin quantum number of one and does not cause chemical shift

(R)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine and its enantiomer (S)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine are also known as Schöllkopf chiral auxiliaries or Schöllkopf reagents, and are used to produce optically pure α-amino acids via asymmetric synthesis. The Schöllkopf reagent can be deprotonated at the prochiral α-carbon, and the resulting enolate is trapped with electrophiles to yield adducts with high (typically > 95% d.e.) diastereoselectivity. The enolate is essentially planar, and the steric bulk of the isopropyl group directs the incoming electrophile to attack from the opposite face, yielding trans adducts. A wide range of electrophiles including alkyl halides, alkyl sulfonates, acyl chlorides, aldehydes, ketones, epoxides, thioketones and enones can be used. Hydrolysis, typically under mild acidic conditions, yields the non-substituted amino acid with high (typically > 95 e.e.) enantiopurity.

2,6-Diaminopurine is a nucleotide analogue that is synthesized from guanosine. It inhibits the enzyme ribonucleotide reductase and blocks the synthesis of DNA precursors, which are necessary for viral replication. 2,6-Diaminopurine has been shown to inhibit hiv infection in tissue culture and animal models by decreasing the levels of nucleotides in cells. This drug can be used as an anti-viral agent against HIV and other retroviruses. 2,6-Diaminopurine has also been shown to be effective against murine sarcoma virus. The compound binds to the enzyme ribonucleotide reductase, which is important for DNA synthesis, and prevents its activity by mimicking adenosine triphosphate (ATP). The binding of 2,6-diaminopurine to ATP results in a coordination geometry that causes a long hydrogen bond with one oxygen

2,4-Dimethoxybenzaldehyde is a synthetic compound that has been shown to have activity against pancreatic lipase. It has been suggested as a potential drug for the treatment of metabolic disorders such as obesity or diabetes. 2,4-Dimethoxybenzaldehyde can be synthesized by reacting ethyl diazoacetate with an aldehyde in the presence of ammonium acetate. This chemical can also be used to produce ethyl esters and compounds belonging to the group of phlorotannins. 2,4-Dimethoxybenzaldehyde has been shown to have antioxidative activity and inhibitory effects on pancreatic lipase.

2,6-Dichloropurine is a nitrogenous base that inhibits the activity of certain enzymes in the body. It has been shown to inhibit protease activity and nitro reductases, which are enzymes that metabolize nitrosamines. 2,6-Dichloropurine also inhibits the synthesis of epidermal growth factor (EGF) and adenosine A3 receptors in vivo. This drug has potent antitumor activity against various cancer cells and is used for the treatment of HIV infections. 2,6-Dichloropurine can be synthesized from 6-fluoro-3-indoxyl-beta-D-galactopyranoside with an intramolecular hydrogen atom.