Semi-synthetic penicillins

Semi-synthetic penicillin antibiotics type of penicillins received synthetic accession of certain chemical groups dedicated to biological way 6-aminopenicillanic acid (APC). This connection was received by Batchelor (F. R. Batchelor, 1959) and TCS. from the culture fluid after growing in her P. cbrysogenum in the absence of some predecessors, and later by enzymatic hydrolysis of various natural penicillins. Obtaining large quantities APC opened broad prospects for the synthesis of new compounds of the type of penicillins, having particular properties.
Among the numerous semi-synthetic penicillins used in chemotherapy of bacterial infections found mainly the following preparations.
1. Propicillin - alpha-fenoximetilpenitsillina, or 6(D)-phenoxybutyryl-aminopenicillanic acid. Applied in the form of potassium salt (synonym: Baycillin, Brocillin, Ultrapen). Stable in the presence of acids, and therefore applies per os. Relatively little sensitive to the action penitsillinazy and active against bacteria strains resistant to penicillin G(G). Is applied at a dose of 200 000 IU 3 times a day.
2. Methicillin sodium salt 2,6-dimethoxyphenylethylamine, or dimethoxybenzonitrile acid (synonym: Gelbenin, Staphcillin, Cinopenil, BBL-1241). The first semi-synthetic penicillin resistant against penitsillinazy, although it is a strong inducer of education of this enzyme. Effective in the treatment of infections caused by resistant P. staphylococci. Sensitive to acids, and therefore not effective in the application of per os. 50 to 100 times less active than penicillin G(G).
3. Ampicillin - D-alpha-aminobenzimidazole, or 6-D-alpha-amino-alpha-phenylacetoacetonitrile acid (synonym: Penbritin, Polycillin, Binotal, BRL-1341). Resistant to acids, has a wide spectrum of action; active against many gram-negative bacteria. Has no penicillinaseproducing and therefore not effective against resistant P. strains of staphylococci. Applies per os in a dose of 1 g 3-4 times a day.
4. Phenoxymethylpenicillin - 6-alpha-fenoximetilpenitsillina acid (synonym Penspek). Resistant to acids, effective per os, is well absorbed from the gastrointestinal tract and creates a higher concentration in the blood than P. Sensitive to the penicillinase and not effective against resistant to penicillin strains of staphylococci.
5. Oxacillin sodium salt 6-D -(5-methyl-3-phenyl-isoxazolyl-4-carbamide) penitsillanovoy acid (synonym: Cryptocillin, Stapenor, Prostaphlin, Besistopen, BRL-1400). Resistant to penitsillinaze and to acids, used per os for treatment of infections caused by resistant P. staphylococci. In view of the rapid excretion by the kidneys should use it in the dose of 500-1000 mg every 4-6 hours.
6. Cloxacillin - 6-(5-methyl-3-ortogiardino - isoxazol-4 - carboxamide) penitsillanovoy acid (synonym: Orbenin, BRL-1621). Resistant to acids and to penitsillinaze. Applies per os approximately the same doses as oxacillin.
7. Climatically - potassium salt 3-4-dichlorophenyl-alpha-metasemicontinuous acid. Resistant to acids, used per os in a dose of 1 to 1.5 g / day (2-3 times in 500 mg every 8 hours); valid only on bacteria that are susceptible to penicillin.
8. Hinzelin - disodium salt C-carboxy-2-chinogaramombe-penitsillanovoy acid. Active against resistant P. strains of staphylococci, as insensitive to penitsillinaze.
9. Nafcillin - sodium salt 6-(2 - ethoxy-1 naftaeco) penitsillanovoy acid (synonym Unipen). Resistant to acids and penitsillinaze; applies per os and parenteral for treatment of infections caused by staphylococci resistant P.
Cm. also Antibiotics.