Carbamates structures

Zinc carbamate complexes are well known, and the structural types and stabilities can be compared with thiocarbamates and dithiocarbamates which are discussed in Sections 6.8.11.1.3 and 6.8.7.1.4482 Carbamates of zinc can be formed from the reaction of carbon dioxide with alkylzinc alkyl amides and further reaction with alkylzinc can give a distorted cubane structure.483 The tetrameric diethylcarbamate species initially formed can also be used to produce monomeric or dimeric carbamate structures in reaction with amines tetramethylethylenediamine forms a monomer [(Me2NCH2)2Zn(02CN(C2H5)2)2] with an octahedral zinc center and pyridine forms a dimer[CsH5NZn2Me(02CN(C2H5)2)3] with tetrahedral zinc centers.484... 

Chemical Name 3-(4-Chlorophenoxy)-l,2-propanediol-l-carbamate Common Name 3-p-Chlorophenoxy-2-hydroxypropyl carbamate Structural Formula ... 

Common Name Methyl-5-benzoyl-2-benzimidazole carbamate Structural Formula ... 

Adducts with methylamine and dimethylamine have also been prepared 47>48>. All of the adducts are stable, crystalline solids which were shown to have the carbamate structure from a variety of observations. Trimethylamine does not react with BH3CO to give a carbamate analog an unstable 1 1 adduct is obtained. 

Further studies indicated that the inhibition was competitive with respect to substrate, and that the rate of enzyme reactivation was very slow (ti/2). These facts, together with the strained carbamate structure, suggested acylation of the active site serine by the carbamate. Indeed, LC-MS analysis of the inhibited enzyme indicated... 

Analysis, infrared (neat), and NMR spectra were in agreement for the proposed structures of (30-34). Based on elemental analysis and NMR spectra the alternate carbamate structure NCKNC(=0)0R had to be considered in reaction 7. However, the carbamate structure was ruled out on the basis of the infrared spectral data. In 30 the presence of C=N and C=N absorption bands at 2170 and 1580 cm-T"7 respectively and the absence of the C=0 absorption band at 1700-1755 cm- furnished conclusive evidence for the proposed structures (30-34). 

Scheme 6. Bioreductive activation through reduction of a nitro group followed by 1,6-elimination and representative related prodrugs. The nitrogen is part of the carbamate structure.

OP insecticides having phosphonate and carbamate structure that contain thioether bonds are good substrates for FMO. These enzymes participate in oxidative desulfuration (P=S P=0) of OPC such as fonofos and phenylfonofos [22, 23]. It has been shown that FMO requires P-C bond in OPC since it acts directly on phosphorus atom, while oxidative desulfuration with P450 occurs on sulfur that is bound to phosphorus (P=S). For that reason parathion and some phosphorodithionates are not FMO substrates. Compounds of trivalent phospho-... 

Only limited carbamate structure-activity relationship studies have been done with regard to comparisons of the inhibitory capacity toward AChE versus BuChE. However, based on structure-activity studies with five Af-methyl carbamates, Loewenstein et aL (1993) concluded that the CM binding site on BuChE is less flexible than the same site on AChE. 

Chemical Name (5-benzoyl-1H-benzimidazol-2-yl)carbamic acid methyl ester Common Name Methyl-5-benzoyl-2-benzimidazole carbamate Structural Formula ... 

Table 11.6 gives typical NH bond positions and is specifically applicable to isocyanate derivatives. The area of absorption in Table 11.6 shows bonded NH (3400-3200cm " ) and free NH (3500-3400 cmThe compounds studied had bonded NH absorptions in the 3310-3380 cm range. This area increased in absorption as the free NH area (3500-3400cmdecreased during a urethane reaction. The carbamate structure was observed to have absorption only in the bonded NH area (3320-3350 cm " in the melt or liquid spectrum, but there was absorption in the free NH or OH range in the KBr spectrum (3490-3440 cm... 

The starting product, the 5,6-dichlorobenzoxazolinone (see Section 9.6) contains the carbonamide or rather the carbamate structure and is a known fungicide especially for the protection of textile material. The introduction of the hydroxymethyl group leads to a compound with an effective spectrum more balanced than that of the starting product (see Table 39). 

Phenprobamate [673-31-4], muscle relaxant, tranquilizer, 188. Phosgenation is the key step in generating the final carbamate structure 188 [138],... 

Zopiclone [43200-80-2], anxiolytic, hypnotic, 240. l-Chlorocarbonyl-4-methylpiper-azine, 238, a key intermediate en route to Zopidone, an API having a carbamate structure, is prepared with phosgene [172, 173]. An improved synthesis of this intermediate has been reported by SNPE [174]. 

The reaction mechanism proposed [15, 16] involves the abstraction of hydrogen atoms from two types of structures a carbamate structure (A) and a tertiary amide structure (B) ... 

By reviewing Chart 1, it is noteworthy to observe the versatility of the carbamate structure. Thus, proper choice of the R, R X and Y groups of the carbamate structure as shown in Chart I led to the discovery of fifteen commercial herbicides, fungicides and insecticides. 

Ma SL, Shen S, Lee H, Yee N, Senanayake C, Nafie LA, Giinberg N (2008) Vibrational circular dichroism of amylose carbamate structure and solvent-induced conformational changes. Tetrahedron Asymmetry 19 2111-2114... 

Carbamates - Structure activity relationships have been studied with respect to toxicity and anticholinesterase activity. 9 The mechanism of acetylcholinesterase inhibition by the carbamates is not entirely clear. 

Carbamates (structure I) represent a class of compounds distinct from A -carbamates (substituents on the nitrogen atom as in structure II). In this chapter only carbamates with varying substituents on the oxygen atom are discussed. 

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