Of macrolide antibiotics

The utility of RCM methodology for the synthesis of open-chain building blocks from a,fi-unsaturated d-lactones is exemplified by the partial syntheses of Cossy aimed for (+)-methynolide (the aglycon of the methymicin family of macrolide antibiotics) [45], and the anticancer agent discodermolide [46], as well as during a recent total synthesis of the highly cytotoxic marine natural depsipeptide apratoxin A by Forsyth and Chen [47]. 

Scheme 78 Novel ring-contraction metathesis of macrolide antibiotics with a 1,3-diene moiety [164]...

For a high-yielding ring contraction in the series of macrolide antibiotics containing a 1,3-diene unit, see Scheme 78... 

McArdell CS, Molnar E, Suter MJF, Giger W (2003) Occurrence and fate of macrolide antibiotics in wastewater treatment plants and in the Glatt Valley watershed, Switzerland. Environ Sci Technol 37(24) 5479-5486... 

Loganathan B, Phillips M, Mowery H, Jones-Lepp TL (2009) Contamination profiles and mass loadings of macrolide antibiotics and illicit drugs from a small urban wastewater treatment plant. Chemosphere 75(l) 70-77... 

Fig. 5.11 Erythromycins erythromycin is a mixture of macrolide antibiotics consisting largely of erythromycin A.

Borisova, S., Zhao, L., Melancon, C.E. et al. (2004) Characterization of the glycosyltransferase activity of desVII analysis of and implications for the biosynthesis of macrolide antibiotics. Journal of the American Chemical... 

Compound 17 is the so-called (+)-Prelog-Djerassi lactonic acid derived via the degradation of either methymycin or narbomycin. This compound embodies important architectural features common to a series of macrolide antibiotics and has served as a focal point for the development of a variety of new stereoselective syntheses. Another preparation of compound 17 is shown in Scheme 3-7.11 Starting from 8, by treating the boron enolate with an aldehyde, 20 can be synthesized via an asymmetric aldol reaction with the expected stereochemistry at C-2 and C-2. Treating the lithium enolate of 8 with an electrophile affords 19 with the expected stereochemistry at C-5. Note that the stereochemistries in the aldol reaction and in a-alkylation are opposite each other. The combination of 19 and 20 gives the final product 17. 

Biological properties of ethylene, 70 598-599 of macrolide antibiotics, 75 302-305 of sutures, 24 216-218 Biological recycling technologies, in wastewater treatment, 25 889t, 895-902... 

Biosynthetic patterns, of macrolide antibiotics, 15 305-306 Biota, circulation of water with, 26 7-12 Biotechnological manufacturing, key characteristics of, ll 440t Biotechnological membrane applications, 15 848... 

Tobback, K., Li, Y.-M., Pizarro, N. A., De Smedt, I., Smeets, T., Van Schepdael, A., Roets, E., and Hoogmartens, J. (1999). Micellar electrokinetic capillary chromatography of macrolide antibiotics separation of tylosin, erythromycin and their related substances.. Chromatogr. A 857, 313-320. 

Zhang, S., Huang, X., Yao, N., and Horvath, C. (2002). Preparation of monodisperse porous polymethacrylate microspheres and their application in the capillary electrochromatography of macrolide antibiotics. /. Chromatogr. A 948, 193—201. 

Lange F, Comelissen S, Kubac D, Sein MM, von Sonntag J, Hannich CB, Golloch A, Heipieper HJ, Moder M, von Sonntag C (2006) Degradation of macrolide antibiotics by ozone a mechanistic case study with clarithromycin. Chemosphere 65 17-23... 

The application of chromatographic methods to analyze the residues of macrolide antibiotics has been very limited. Moats (85) listed four TLC and one HPLC method for tylosin and one TLC method for erythromycin. In a comparison of the HPLC and microbiological methods for incurred residues in swine, the HPLC method was more sensitive and usually gave higher results (86). 

There are also known macrolides with a 12-membered lactone ring, which received the name of patulolides, as well as those with a 16-membered lactone ring, which are called isenamycins. Today, there are about 100 compounds that make up this group of macrolide antibiotics, and they are generally produced by streptomycetes. 

Growth promoters -tetracyclines as [ANTIBIOTICS - TETRACYCLINES] (Vol 3) -use of macrolides [ANTIBIOTICS - MACROLIDES] (Vol3) -as veterinary drugs [VETERINARY DRUGS] (Vol 24)... 

B Delepine, D Hurtaud, P Sanders. Multiresidue method confirmation of macrolide antibiotics in bovine muscle by liquid chromatography-mass spectrometry. J AOAC Int 79 397-404, 1996. 

Saiman L. The use of macrolide antibiotics in patients with cystic fibrosis. Curr Opin Pulm Med. 2004 10 515-523. 

Quiros LM, Carbajo RJ, Brana AF et al (2000) Glycosylation of macrolide antibiotics. Purification and kinetic studies of a macrolide glycosyltransferase from Streptomyces antibioticus. J Biol Chem 275 11713-11720... 

Kreuzman AJ, Turner JR, Yeh WK (1988) Two distinctive O-methyltransferases catalyzing penultimate and terminal reactions of macrolide antibiotic (tylosin) biosynthesis. Substrate specificity, enzyme inhibition, and kinetic mechanism. J Biol Chem 263 15626-15633... 

Yang, S. and K.H. Carlson. 2004. Solid-phase extraction-high-performance liquid chromatography-ion trap mass spectrometry for analysis of trace concentrations of macrolide antibiotics in natural and waste water matrices. J. Chromatogr. A 1038 141-155. 

At the start of the analysis when you have done no more than recognise the FGs and note special features (such as rings) or easy disconnections, note also the number of chiral centres and their relationship to each other. The Prelog-Djerassi lactone 1 is an important intermediate in the synthesis of macrolide antibiotics.1 It has a six-membered lactone ring and a separate carboxylic acid. More to the point, it has four chiral centres la. Three (1-3) are adjacent and one (5) separate. We might say that the three adjacent centres should be easy to control because they are next to each other but that we might have trouble with C-5. Another way to look at it is to say that the three round the six-membered ring (2, 3 and 5) should be easy to control, as the... 

A Arisawa, N Kawamura, H Tsunekawa, K Okamura, H Tone, R Okamoto. Cloning and nucleotide sequences of two genes involved in the 4"-0-acylation of macrolide antibiotics from Streptomyces thermotolerans. Biosci Biotechnol Biochem 57 2020-2025, 1993. 

S. Ohmura, Y. Suzuki, A. Nakagawa, and T. Hata, Fast liquid chromatography of macrolide antibiotics, J. Antibiot., 26 794 (1973). 

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