ALPROSTADIL ETHYL ESTER is a prodrug of PGE1 with an improved transdermal permeation due to the esterification

N-Acetyl-α-D-glucosamine (alpha-GlcNAc) is a major component of complex carbohydrates, that has been found in N- and O-glycans and glycolipids. Glycosaminoglycans and the glycosylphosphatidylinositol anchor of membrane-bound glycoproteins also contain GlcNAc moieties. GlcNAc is derived from the degradation of glycoconjugates by glycosidases and from nutritional sources. GlcNAc is converted into GlcNAc-6-phosphate by the N-acetylglucosamine kinase. GlcNAc-6-phosphate can enter a catabolic pathway that ultimately leads to the formation of fructose-6-phosphate, or it can enter an anabolic pathway leading to the formation of UDP-GlcNAc.

Ethyl 2-oxo-4-phenylbutyrate is useful for the synthesis of the important chiral precursor for angiotensin-converting enzyme (ACE) inhibitors.

6-Methoxy-2-naphthalenecarboxaldehyde is a substrate of aldehyde dehydrogenase enzymes (class I, class II and class III). It was examined as indicator of the aldehyde dehydrogenase (ALDH) activity in human tissue homogenates and accessible body fluids from patients with viral and toxic liver injuries, and tumors. As intermediate, it was used in organic synthesis of enantiomerically enriched R- and S-6-MONCH- (OH)CN and fluorescent substrates for inhibition studies relating to hypertension and vascular inflammation.

6-amino-penicillanic acid is a common parent amine of various penicillins. 6-amino-penicillinic acid possesses definite antibacterial properties but these are much lower order than these of benzylpenicillin. It is destroyed by penicillinase (Beta-lactamase). The first penicillins to appear as derivatives of 6-APA were in fact phenethicillin and propicillin.

Hypoxanthine is a naturally occurring purine derivative and a reaction intermediate in the metabolism of adenosine and in the formation of nucleic acids by the salvage pathway. Hypoxanthine is a necessary additive in the certain cell, bacteria, and parasite cultures as a substrate and nitrogen source. For example, it is commonly a required reagent in malaria parasite cultures, since Plasmodium falciparum requires a source of hypoxanthine for nucleic acid synthesis and energy metabolism.

3-Tyrosine, in contrast to the para isomer, is readily racemized. The majority of the load was metabolized to m-hydroxyphenylacetic acid but m-hydroxymandelic acid and 3,4-dihydroxyphenylacetic acid were also detected. Low circulating levels of m-tyrosine in the plasma suggest that most of the load is held due to a first pass effect somewhere in the enterohepatic system and that this portion of the load is not in equilibrium with the plasma m-tyrosine. The metabolism of a m-tyrosine may give further insight into the deficiencies of the phenylalanine hydroxylating system found in the various phenotypes of phenylketonuria. 3-Tyrosine has been used experimentally as a substitute for L-DOPA in the treatment of Parkinsonism. 3-tyrosine mimics the action of Dopa in two experimental animal models. It was also obvious from the experiments with d,l- and l-m-tyrosine that only the l-isomer (3-Tyrosine) is active.

7-aminocephalosporanicacid (7-ACA) is convenient starting material for the industrial production of various kinds of semisynthetic cephalosporin antibiotics. In many cases, chemical modifications at the C-7 position is required. Industrially, 7-ACA is derived by chemical or enzymatic deacylation from cephalosporin C, which is fermentatively produced by Acremonium chrysogenum. 7-ACA is a stable only at neutral pHs, enzymatic manipulations are desirable for chemical modifications in the production of cephalosporin related compounds.

Paritaprevir is a potent inhibitor of the NS3/4A protease that rapidly and consistently suppresses HCV. Paritaprevir is metabolized by the Cytochrome P450 isoform 3A (CYP3A); therefore, ritonavir was used concurrently to increase plasma concentrations and to prolong the half-life of this agent allowing for once-daily dosing. Several antiviral regimens combining paritaprevir with other agents have shown impressive results, tolerable side effects, and importantly, provided support of ‘all-oral’ interferon-free regimens against HCV. Paritaprevir monotherapy is discontinued now but paritaprevir is used as a component of Viekira Pak and Technivie for the treatment of patients with genotype 1 chronic hepatitis C virus (HCV) infection.