Synthesis and properties of bilirubin analogs with one propionic acid group

Unsymmetric bile pigment analogs of mesobilirubin-XIIIα and mesobilirubin-IVα were synthesized following oxidative coupling of dipyrrinones: methyl xanthobilirubinate with kryptopyrromethenone; methyl ψ-xanthobilirubinate with kryptopyrromethenone.     

Synthesis,structure, and complexation properties of hydroxybenzyl analogs of diethylenetriaminepentaacetic acid

As part of continuous search for new chelating agents for transition metal ions, a practical method for the preparation of hydroxybenzyl derivatives of diethylenetriaminepentaacetic acid (DTPA) has been developed in this study. N,N″-bis(2-hydroxybenzyl)diethylenetriamine-N,N′,N″-triacetic acid (HBDTTA) and four other hydroxybenzyl derivatives of DTPA have been synthesized. The structures and chelating capacity of three ligands with Fe³⁺ have been predicted using density functional theory-based calculations at the BP86/TZVP level within a previously developed and tested computational procedure. The results show that like DTPA, HBDTTA can adopt several different six- and seven-coordinate complex structures. The good stability of Fe³⁺ complexes of two HBDTTA derivatives indicates that HBDTTA-type ligands can be modified by removing some of their functional groups without greatly affecting their metal-binding efficiency.     

Synthesis and properties of analogs of pyridoxal

A method for the synthesis of analogs of pyridoxal-2-norpyridoxal, 6-methyl-2, 4-pyridoxal, and 6-methylpyridoxal—has been worked out. The reaction of 5-ethoxyoxazoles with maleic diesters gave diesters of substituted 3-hydroxycinchomeric acids, which were converted by reduction with lithium aluminum hydride into analogs of pyridoxine. The latter were oxidized with magnesium dioxide to the corresponding analogs of pyridoxal. The oximes of the aldehydes and their Schiff's bases with p-phenetidine have been obtained. Analogs of pyridoxamine have been obtained by the hydrogenation of the oximes. The UV absorption spectra of the compounds and the ratios of the ionic forms in aqueous solutions have been studied.     

Synthesis and properties of analogs of pyridoxal

A method for the synthesis of analogs of pyridoxal-2-norpyridoxal, 6-methyl-2, 4-pyridoxal, and 6-methylpyridoxal—has been worked out. The reaction of 5-ethoxyoxazoles with maleic diesters gave diesters of substituted 3-hydroxycinchomeric acids, which were converted by reduction with lithium aluminum hydride into analogs of pyridoxine. The latter were oxidized with magnesium dioxide to the corresponding analogs of pyridoxal. The oximes of the aldehydes and their Schiff's bases with p-phenetidine have been obtained. Analogs of pyridoxamine have been obtained by the hydrogenation of the oximes. The UV absorption spectra of the compounds and the ratios of the ionic forms in aqueous solutions have been studied.     

Synthesis of fusaric acid and its analogs

Summary 1. A new method for synthesizing fusaric acid and its analogs has been proposed which starts from 2-methyl-5-ethynylpyridine; this is alkylated and the hydrogenated 2-methyl-5-alkynylpyridines are oxidized to the corresponding 5-alkylpicolinic acids.2. The mass-spectroscopic behavior of the 2-methyl-5-alkylpyridines has been studied.Khimiya Prirodnykh Soedinenii, Vol. 3, No. 2, pp. 134–137, 1967     

Synthesis and properties of styrenetricarbonylchromium and its analogs

The methods of synthesis and the reactivity of styrenetricarbonylchromium and its analogs as model objects for the study of the effect of the metal atom on the reactivity of the monomer -bond and the aromatic ring are described systematically and discussed. These compounds are unique initial substrates for the synthesis of metal-containing polymers and for the preparation of optical stereoisomers and materials for nonlinear optics.     

Synthesis and properties of heterocyclic analogs of isoflavones

The condensation of cyanomethyl derivatives of furan and benzofuran with di- and trihydric phenols has given the corresponding 2,4-dihydroxy- and 2,4,6-trihydroxy--heterylacetophenones. The latter have been converted by reaction with acid anhydride, ethoxalyl chloride, and trifluoroacetic anhydride into 3-heterylchromones with methyl, trifluoromethyl, and ethoxycarbonyl groups in position 2.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1202–1208, September, 1973.     

Synthesis and properties of thiolactam analogs of pyrromethenones

Thiolactam analogs of kryptopyrromethenone and xanthobilirubic acid methyl ester were prepared from the parent pyrromethenone using Lawesson's reagent and are shown to form dimeric association complexes through intermolecular hydrogen bonding.     

Synthesis of analogs of lysergic acid diethylamide

Conclusions A number of N-methyl-N[(-(-Indolyl)ethyl]glycine amides, representing analogs of lysergic acid diethylamide, were obtained.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2613–2614, November, 1972.     

Synthesis of phosphinic and phosphoric analogs of aspartic acid

Approaches to the synthesis of 1-amino- and 2-amino-2-carboxyethylphosphinic and-phosphoric acids have been studied. A convenient method for the preparation of phosphinic acids is the reactions of ethyl diethoxymethylphosphonite with ethyl acetamidomethylenemalonate and ethyl 2-acetamidoacrylate.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 2066–2069, August, 1996.     

Synthesis and properties of heterocyclic analogs of 4-azidochalcone

A study has been made of the spectral and photochemical properties of a series of heterocyclic analogs of 4-azidochalcone, specifically the pyridine, quinoline, isoquinoline, and quinoxaline derivatives. It has been shown that the absorption spectra of most of the 4-azidocinnamoylarenes are shifted bathochromically in comparison with 4-azidochalcone. The quantum yields of photodissociation of the compounds that were investigated were found to vary within the limits 0.70±0.15. With steric hindrance for the planar conformation of the molecule, a hypsochromic shift of the absorption spectra is observed, along with a slight decrease of the quantum yield.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1340–1343, October, 1991.     

Synthesis and some properties of topochemical analogs of valinomycin

Chemistry of Natural Compounds -     

Synthesis and properties of polymeric analogs of ionic liquids

A number of methacrylate ionic monomers with different structures and mobilities of ionic centers were synthesized. The free-radical polymerization of these monomers in solution affords high-molecular-mass (M _sD = 0.5 to 2.5 × 10⁶) thermally stable (T _dec > 170°C) polyelectrolytes or cationic or anionic “polymeric ionic liquids.” The conductivities of polycation- and polyanion-derived coatings are (7.4 × 10^?10)?(7.6 × 10^?7) and (4.9 × 10^?10)-(1.6 × 10^?7) S/cm (25°C), respectively. As exemplified by poly(1-[3-(methacryloyloxy)propyl]-3-methylimidazolium bis[(trifluoromethanesulfonyl)imide]), the molecular mass and glasstransition temperature of the polymer affect the ionic conductivity of the film coating. The transition from linear polyelectrolytes to crosslinked systems based on ionic monomers and poly(ethylene glycol dimethacrylate) 750 leads to the formation of elastic films featuring satisfactory strength, reduced glass-transition temperatures (?8 to +15°C), and increased ionic conductivity (up to 3.2 × 10^?6 S/cm (25°C)).     

Synthesis and evaluation of simplified functionalized bongkrekic acid analogs

Bongkrekic acid (BKA) is a strong inhibitor of adenine nucleotide translocase (ANT), inducing inhibition of adenosine triphosphate synthesis. We designed and synthesized simplified benzene-ring-containing BKA analogs. The key reaction is the one-pot double Sonogashira reaction, which forms the main skeleton. The analogs were efficiently synthesized in 8–10 longest linear sequence steps. This synthetic method can be applied for the preparation of other analogs having different combinations of carbon chain lengths. Furthermore, the allyloxy group on the benzene ring can be easily replaced by other functional groups. Our preliminary biological evaluation based on mitochondrial inhibitory effects revealed the high potency of the analogs bearing the same carbon chain length as that of BKA. In particular, the prefunctionalized analogs are potential ANT inhibitors.