Aldehydes antibacterial activity

A method for the synthesis of long-chain aminophosphinic acids having surface-active and antibacterial activity followed the procedure developed by Schmidt [182]. It is based on the condensation of the hypophosphite salt of a primary amine with an aldehyde or ketone [183], as shown in Eq. (108) ... 

OE222 Bisignano, G., M. G. Lagana, D. Trombetta, et al. In vitro antibacterial activity of some aliphatic aldehydes from Olea europaea L. FEMS Microbiol Lett 2001 198(1) 9-13. 

In the reaction of a simple ketone enolate with a chiral aldehyde, the use of a zinc enolate may offer advantages in terms of facial selectivity with respect to the use of a lithium enolate. This is exactly the result recorded in the condensation of the kinetic enolate of 2-undecanone 140 with 141, the key step in a total synthesis of (-l-)-preussin 142, a fermentation product with antifungal and antibacterial activity (equation 77)169. While 2-undecanone Li enolate did not display stereocontrol when added to 141, an acceptable syn diastereoselectivity was displayed by the Zn enolate 140. 

A one-pot efficient method for the synthesis of derivatives 67 and 68 by condensation reaction of barbituric acids, lH-pyrazol-5-amines and aldehydes under solvent-free conditions has been reported (Scheme 16) [39]. These products were evaluated in vitro for their antibacterial activities against E. coli (ATCC 25922), P. aeruginosa (ATCC 85327), Enterococcus faecalis (ATCC 29737), Bacillus subtilis (ATCC 465), Bacillus pumilus (PTCC 1114), Micrococcus luteus... 

Other reductive aminations of tylosin-related macrolides have been reported, including the synthesis of dimeric moieties which retain antibacterial activity [92,93]. Other modifications of the aldehyde group include a variety of hydrazone derivatives, reduction products, and C-alkylated analogues [83, 94]. 

Coumarins. - There is interest in the synthesis of 3-substituted coumarins cyclization of substituted salicylaldehydes with cyanoacetamide, followed by treatment with phosphoryl chloride in DMF, has given coumarin-3-carbonitriles. High yields of 3-phenylcoumarins were obtained when ortho-hydroxy-aldehydes or -ketones were treated with phenylacetyl chloride-potassium carbonate.When cyclohexane-1,3-diones (187) were condensed with triethyl orthoformate and either urea and thiourea and the initial product (188) was allowed to condense with nitriles, the 3-carboxamide (189) was obtained in good yield.The antibacterial activity of some sulphones has prompted the synthesis of 3-arylsulphonyl-coumarins by oxidation of sulphides. ... 

The 18-dihydro compounds showed significantly reduced antibacterial activity. It is suggested that the aldehyde group at C-18 is one of the functional groups essential for the biological activity of the macrolide. 

The poly-N-alkyl- and hexa-N-acyl derivatives of neomycin and paromomycin fail to show activity, but the hexa-N-methane-sulfonates and -sulfina-tes are claimed to be active and less toxic. 6 - and 6" -N alkyl- and N-alkylaryl-neomycins and -paromomycins have been prepared from the Schiffs bases by reduction with NaBH4 Some of the alkylaryl compounds show a slightly improved activity the alkyl derivatives are ineffective. The hexa-N-benzylneomydns prepared from neomycin, aromatic aldehydes and NaBH4, as well as the corresponding paromomycins, synthesized by means of catalytic reduction of the Schiffs bases, have reduced antibacterial activity. The Schiffs bases of paromomycin show in vitro the same activity as the parent compoimd, obviously because of the ease of hydrolysis. 

In a different approach to the preparation of the P-hydroxy-a-amino acids required for cyclization to p-lactams, Hanessian [28, 80] employed 2-amino-2-deoxy-D-glucose, recognizing that the configuration of the amino group in this chiron is that required for the C-3-amino group of antibacterially active p-lactams. The amino sugar was converted to aldehyde 147 via thioacetal 146... 

Kidwai et al. have synthesized 3-formyl-2-(3-hydroxy-l,4-naphthoquinon-2-yl)-quinoline (7) by the reaction of aldehydes (1) with 2-hydioxy-l,4-naphthoquinone (6) in basic alumina using MWI (Scheme 6.3). The synthesized compound showed promising antibacterial activity [39]. 

Nirmal et al. have synthesized biquinoline adducts (18) in high yields by the cycli-zation of [(2-chloro-3-quinolyl)methylene]methane-l,l-dicart>onitriles (16), which was provided from reaction between aldehyde (1) and malononitrile, with 3-aryl-amino-5,5-dimethyl-cyclohex-2-en-l-ones (17) under MWI catalysed by 4-(A7, N-dimethylamino)pyridine (DMAP Scheme 6.8). The synthesized compounds were screened for their antifungal and antibacterial activities [46]. 

Bronopol has a broad spectrum of antibacterial activity and belongs to the group of aldehyde-releasers as well as to the group of activated halogen-compounds. It is widely used as a preservative of pharmaceutical and cosmetic products (Croshaw et al., 1964 Storrs Bell, 1983). Another important emerging application is the use as a preservative in the filler and pigment industry (e.g. calcium carbonate slurries). 

Since modification at C-3 of the cephalosporin structure has led to derivatives with improved antibacterial activity, this area has received a great deal of attention. A key intermediate for C-3 modification is the aldehyde (65 e). For example, the 3,4-dicarboxylic acid (66) was obtained from (65) via a seven-step synthesis. The diacid in turn was converted into a number of C-3-modified derivatives, e.g. (67), (68). The dipolar iV-methylnitrone (69), resulting from the reaction of... 

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