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Sulfonamide tolerances

The substrate scope is limited, as electron-withdrawing groups (X = p-N02 or p-CF3) on the aromatic substituent are not tolerated. However, this route does provide valuable intermediates to unnatural a-amino phosphonic acid analogues and the sulfimine can readily be oxidized to the corresponding sulfonamide, thereby providing an activated aziridine for further manipulation, or it can easily be removed by treatment with a Grignard reagent. [Pg.26]

Because renal impairment is common in older adults the nurse should give the sulfonamides with great caution. There isan increased danger of the sulfonamidescausng additional renal damage when renal impairment is already present. An increase of fluid intake up to 2000 mL (if the older adult can tolerate this amount) decreases the risk of crystals and stones forming in the urinary trad. [Pg.63]

The antibiotic and sulfonamide ophthalmics are usually well tolerated, and few adverse reactions are seen. Occasional transient irritation, burning, itching, stinging, inflammation, or blurring of vision may occur. With prolonged or repeated use, a superinfection may occur. [Pg.627]

Several catalytic systems have been reported for the enantioselective Simmons Smith cyclopropanation reaction and, among these, only a few could be used in catalytic amounts. Chiral bis(sulfonamides) derived from cyclo-hexanediamine have been successfully employed as promoters of the enantioselective Simmons-Smith cyclopropanation of a series of allylic alcohols. Excellent results in terms of both yield and stereoselectivity were obtained even with disubstituted allylic alcohols, as shown in Scheme 6.20. Moreover, this methodology could be applied to the cyclopropanation of stannyl and silyl-substituted allylic alcohols, providing an entry to the enantioselective route to stannyl- and silyl-substituted cyclopropanes of potential synthetic intermediates. On the other hand, it must be noted that the presence of a methyl substituent at the 2-position of the allylic alcohol was not well tolerated and led to slow reactions and poor enantioselectivities (ee<50% ee). ... [Pg.226]

In 1994, only 15% of EPA method validations (tolerance method validation and environmental chemistry method validations) that involved GC were carried out using GC/MS. In 2002, this number is reversed in that 85% of the GC methods that were validated by both programs used GC/MS. Many of the compounds investigated in these method trials were polar compounds, and hence these compounds required derivatization in order to be amenable to GC. One common methylating agent is (trimethylsilyl)diazomethane, which is used, for example, to methylate the sulfonamide flumetsulam. As opposed to HPLC/MS, where derivatization is often not necessary, the GC/MS procedure involves an extra step to methylate this compound, under dry conditions, prior to determination by GC/MS. [Pg.762]

The use of non-sulfapyridine-based aminosalicylates has led to greater tolerability. Although the adverse effects are similar to those of sulfasalazine, they occur at a much lower rate. Olsalazine, in particular, is associated with a higher incidence of secretory diarrhea. These agents can also be used safely in patients with a reported sulfonamide allergy. [Pg.287]

The ruthenium carbene catalysts 1 developed by Grubbs are distinguished by an exceptional tolerance towards polar functional groups [3]. Although generalizations are difficult and further experimental data are necessary in order to obtain a fully comprehensive picture, some trends may be deduced from the literature reports. Thus, many examples indicate that ethers, silyl ethers, acetals, esters, amides, carbamates, sulfonamides, silanes and various heterocyclic entities do not disturb. Moreover, ketones and even aldehyde functions are compatible, in contrast to reactions catalyzed by the molybdenum alkylidene complex 24 which is known to react with these groups under certain conditions [26]. Even unprotected alcohols and free carboxylic acids seem to be tolerated by 1. It should also be emphasized that the sensitivity of 1 toward the substitution pattern of alkenes outlined above usually leaves pre-existing di-, tri- and tetrasubstituted double bonds in the substrates unaffected. A nice example that illustrates many of these features is the clean dimerization of FK-506 45 to compound 46 reported by Schreiber et al. (Scheme 12) [27]. [Pg.60]

Although the ruthenium allenylidene complexes 2 have not yet been as comprehensively studied as their carbene counterparts, they also seem to exhibit a closely related application profile [6]. So far, they have proven to tolerate ethers, esters, amides, sulfonamides, ketones, acetals, glycosides and free secondary hydroxyl groups in the substrates (Table 1). [Pg.60]

The problem of the nucleophilicity of amides in glycosylation reactions is not limited to the sulfoxide method and has been shown to result in the formation of glycosyl imidates from intermolecular reaction with activated donors. It appears that this problem may be suppressed by the prior silylation of the amide [348,349]. Accordingly, it may be sufficient to operate the sulfoxide method with an excess of triflic anhydride when amides are present so as to convert all amides into O-triflyl imidates, which are then hydrolyzed on work-up. Despite these problems, several examples have been published of successful sulfoxide glycosylation reactions with acceptors carrying remote peptide bonds [344,345] and with donors coupled to resins via amide-based linkages [346,347], with no apparent problems reported. Sulfonamides and tertiary amides appear to be well tolerated by the sulfoxide method [340,350],... [Pg.257]

With this revision in our original plans, both alkenes and allenes were found to undergo efficient cycloadditions to produce cyclooctenone products in a new [6+2] cycloaddition process. This novel cycloaddition has been shown to proceed efficiently with alkenes tethered with sulfonamide, ether, or geminal diester Hnkers (Tab. 13.15, see page 294). Isomerization of the olefin, a potential competing reaction in this process, is not observed. Methyl substitution of either alkene in the substrate is well tolerated, resulting in the facile construction of quaternary centers. Of mechanistic importance, in some cases cycloheptene byproducts were isolated from [6+2] cycloaddition reactions in addition to the expected cyclooctenone products (that is, entries 3 and 4). [Pg.293]

Treatment of uncomplicated urethral, endocervical, or rectal Chlamydia trachomaticinfections- As an alternative regimen to doxycycline or tetracycline (or if erythromycin is not tolerated), sulfisoxazole 500 mg 4 times/day for 10 days or equivalent sulfonamide course. [Pg.1700]

Table 13.1 Samples Exceeding Tolerances for Antibiotics and Sulfonamides over the Period 1976-1978 in the United States... Table 13.1 Samples Exceeding Tolerances for Antibiotics and Sulfonamides over the Period 1976-1978 in the United States...
Figure 30. The threading synthesis of [2]rotaxanes tolerates the expansion of the cavity and the alteration of the structure of the sulfonamide wheel 65. Figure 30. The threading synthesis of [2]rotaxanes tolerates the expansion of the cavity and the alteration of the structure of the sulfonamide wheel 65.

See other pages where Sulfonamide tolerances is mentioned: [Pg.537]    [Pg.468]    [Pg.275]    [Pg.204]    [Pg.157]    [Pg.233]    [Pg.1463]    [Pg.243]    [Pg.206]    [Pg.130]    [Pg.55]    [Pg.464]    [Pg.467]    [Pg.163]    [Pg.196]    [Pg.196]    [Pg.154]    [Pg.9]    [Pg.243]    [Pg.82]    [Pg.427]    [Pg.772]    [Pg.153]    [Pg.370]    [Pg.191]    [Pg.91]    [Pg.82]    [Pg.196]    [Pg.22]    [Pg.129]    [Pg.119]    [Pg.121]    [Pg.213]    [Pg.112]    [Pg.191]   
See also in sourсe #XX -- [ Pg.89 , Pg.242 ]




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