Prefixes amides

Amide R—CONH2 0 II / NH2 Common acid prefix + amide formamide Alkane prefix + -amide methanamide... 

A-substituted primary amides are named either (1) by citing the substituents as N prefixes or (2) by naming the acyl group as an N substituent of the parent compound. For example. 

Acyl derivatives, RCO—NH—OH and HjN—O—CO—R, are named as A-hydroxy derivatives of amides and as O-acylhydroxylamines, respectively. The former may also be named as hydroxamic acids. Examples are A-hydroxyacetamide for CH3CO—NH—OH and O-acetylhydrox-ylamine for HjN—O—CO—CH3. Further substituents are denoted by prefixes with O- and/or A-locants. For example, C5H5NH—O—C2H5 would be O-ethyl-A-phenylhydroxylamine or A-ethox-ylaniline. 

Another topical anesthetic, similar to benzocaine, is lidocaine, which is used to relieve the pain of shingles (herpes zoster) infections. Lidocaine is called an amide anesthetic, because it is not an ester (the alcohol is replaced by an amide, the nitrogen group). Amide anesthetics are metabolized by the liver, and are less prone to cause allergic reactions. If an anesthetic has the letter i in the prefix (lidocaine, prilocaine, bupivacaine), it is an amide anesthetic. 

If there are two hydrogen atoms (and no alkyl groups) attached to the nitrogen atom, the compound is a primary amide and needs no other prefixes. 

When the amide nitrogen is substituted with lower-ranking groups than the acyl group, the substituents are designated as prefixes. The letter N is used to show that the substitution is on nitrogen ... 

The naming of amides is summarized in Section 7-7D. The points to remember are that they generally are named either as (i) alkanamides, in which the prefix alkan(e) is determined by the longest carbon chain that includes the... 

To name a primary amide, first name the corresponding acid. Drop the -ic acid or -oic acid suffix, and add the suffix -amide. For secondary and tertiary amides, treat the alkyl groups on nitrogen as substituents, and specify their position by the prefix N-. 

The PAs in the prefixes for the naming of the membranes stand for polyamide. Thus, the membranes referred to are polyamide membranes. PA membranes contain the amide group [NH2] it is for this component that they are called polyamide membranes. The formulas for the NS-100, NS-300, and the FT-30 membranes contain the amide group, thus, they are polyamide membranes. The NS-200 is not a polyamide membrane. 

Name the alkyl group (or groups) bonded to the N atom of the amide. Use the prefix N- preceding the name of each alkyl group to show that it is bonded to a nitrogen atom. This becomes the first part of the name. 

For 3° amides, use the prefix di- if the two alkyl groups on N are the same. If the two alkyl groups are different, alphabetize their names. One N-" is needed for each alkyl group, even if both R groups are identical. 

By prefixing the Water-PRESS subunit to the beginning of a COSY sequence, excellent water suppression can be obtained. In Fig. 21 the amide regions of COSY spectra of lysozyme acquired using presaturation and Water-PRESS are compared. Since Water-PRESS does not bleach out the a-protons under the water resonance, there are numerous amide cross-peaks close to the water frequency that are only visible in the COSY acquired using Water-PRESS. 

Fig. 2L Amide regions of COSY spectra of the lysozyme solution acquired using (A) presaturation of the water resonance prior to the COSY sequence and (B) the Water-PRESS sequence prefixed to the COSY sequence. The water resonance was at 4.51 ppm. The effects of presaturation on the resonances near and under the water resonance are clearly seen by the absence/diminution of the cross-peaks having a-proton resonances around 4.5 ppm.

For secondary, tertiary, and quarternary amines, the naming convention is a bit different, but the suffixes are the same. For symmetrical amines, the di" or "tri" prefix is used depending on whether there are 2 or 3 substituents. For example, dipropylamine or triphenylamine. For asymmetric amines, the parent chain gets the -amine suffix. This name is then prefixed with N- (indicating the nitrogen bond) and the substituent group name, for each substituent, using alphabetic order for tertiary amides. For example, N-ethyl-N-methyl-propylamine, not N-methyl-N-ethyl-propylamine. 

When naming secondary and tertiary amides, the groups attached to the (-NH2) group are indicated by the prefix N-, and these group names prefix the name of the corresponding primary amide. ... 

Since several newly-discovered alkaloids contain the 9/S,19-cyclo-ll-oxo conjugated system, it has been proposed to use the prefix cycloxo in naming them. Further, since many alkaloids contain the amide function, it has become customary to indicate this function in their names. Thus baleabuxine and the baleabuxidines are named as follows ... 

Substituents on the nitrogen are placed as prefixes and are indicated by N- followed by the name of the substituent. There are no spaces between the prefix and the amide name. For example ... 

Only the last of these, trithiocarbonic acid, is known in the free state,741 the others existing only as salts, chlorides, esters, and amides. In the light of modern practice, these acids are here named thio-, dithio-, and trithio-car-bonic acid according to the number of sulfur atoms present in the molecule the hypothetical acids may be distinguished by 5- and/or O-prefixes, e.g., the first is thiocarbonic 0,5-acid and the third is dithiocarbonic 5,5-acid for derivatives of these acids, O- and 5-prefixes are also used, when necessary, before the names of atoms or groups replacing hydrogen of the acid. 

The German prefix 0x0 is preferable to keto since one of the carbonyls is in an amide grouping. It is not a diketone but a ketoamide. 

Polyamide resins are linear condensation polymers with a high degree of crystallinity with repeating amide (-CO-NH-) links in their molecular chain. The number of carbon atoms between the amide bonds in the main backbone designates the number after the prefix PA . There are, however, two distinct types of polyamides with the following chemical formulas [1] ... 

If the nitrogen atom of the amide is bonded to an allgrl or aryl group, the group is named, and its location on nitrogen is indicated by the prefix N-. 

However, as noted above in the examples shown, if the nitrogen atom of the amide bears substituents, they are (a) located by placing an N for each substituent on nitrogen as a hyphen-separated prefix along with (b) the name, as a radical ending in yl, of the substituent, or substituents. If more than one substituent is present, they are named in alphabetical order if nonidentical, or with the further prefix di if they are identical. 

As lactones are cyclic esters, so lactams are cyclic amides. Again, as was the case with lactones, the nomenclature of the lactams is based on the use of Greek letters to show ring size, substitution of nitrogen for carbon in a cyclic array (thus using the prefix azacyclo ), or the Hantzsch-Widman system (vide supra). Some examples follow in Table 5.14. 

The classification into primary, secondary and tertiary compounds can also be applied to amides. Secondary and tertiary amides are named rather like amines, in that the other alkyl group attached to the nitrogen atom is prefixed by an N for example, N-methylethanamide (Figure 10.43) is a secondary amide, whereas N,N dimethylpropanamide, CH3CH2CON(CH3)2, would be a tertiary amide. 

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