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PubMed1985

Thresholds of the dog for detection of inhaled eugenol and benzaldehyde determined by electroencephalographic and behavioral olfactometry.

Electroencephalographic olfactometry and behavioral olfactometry were developed to evaluate objectively the olfactory function of 12 dogs. These techniques were used to determined normative thresholds for benzaldehyde, a mixed olfactory and trigeminal stimulant, and eugenol, a suspected pure olfactory stimulant, in 12 dogs. Both techniques were effective in obtaining a mean threshold for clinically normal dogs. Electroencephalographic olfactometry was demonstrated to be more sensitive than was behavioral olfactometry. The techniques measured olfactory function by failure to evoke responses in dogs after ablation of olfactory mucosa. The contribution of trigeminal stimulation to the thresholds was not determined.

Animals↗
PubMed1983

Differential enhancement of cytotoxicity by combination of the carcinostatic agent benzaldehyde and hyperthermia in simian virus 40-transformed and normal cell lines.

The effect of the carcinostatic drug benzaldehyde (BA) on hyperthermia-induced cytotoxicity was studied in various types of cultured mammalian cell lines by colony formation assay. The treatment of HeLa cells with nontoxic doses of BA (1 to 4 mM) at 42 and 43 degrees for up to 3 hr induced enhancement of cell killing. BA-induced enhancement of hyperthermic cell killing was much greater in SV40-transformed rat fibroblast cells than in the untransformed cell line. This BA-induced differential enhancement of hyperthermic cell killing increased as the time and dose of BA treatment were increased at elevated temperatures. For example, BA (2 mM) treatment for 4 hr at 42 degrees decreased the survival of transformed cells to 2 X 10(-4), but decreased the survival of untransformed cells to only 0.1. Furthermore, BA (4 mM) treatment for 2 hr at 42 degrees reduced the survival of transformed cells to less than 10(-5), but reduced the survival of untransformed cells to 5 X 10(-2). Differential enhancement of hyperthermic cytotoxicity by BA was also evident between normal human diploid fibroblast W138 cells and its SV40-transformed cell line, although the magnitude of the enhancement was less than that observed with rat cell lines. The determination of BA remaining in the medium after incubation with transformed and untransformed rat cells at 37, 42, and 43 degrees suggested that greater amounts of BA reacted with or were consumed by transformed cells irrespective of temperature.

Animals↗
PubMed1984

Binding of NADH to horse liver alcohol dehydrogenase: dependence on concentration of benzaldehyde and benzyl alcohol.

Equilibrium titration measurements of NAD+ and NADH in the presence of stoichiometric amounts of liver alcohol dehydrogenase (10(-6)N less than enzyme = coenzyme less than 10(-4)N) have been carried out by using the couple of substrates benzyl alcohol-benzaldehyde, at pH 7.0 and 8.75, in the absence and in the presence of isobutyramide. The results obtained have been unsuccessfully analyzed on the basis of the widely accepted compulsory order model which assumes functional equivalence and independence of the enzyme sites.

Alcohol Dehydrogenase↗
PubMed1983

New arylsulfonylhydrazones of substituted benzaldehydes as anticancer agents.

Nineteen new arylsulfonylhydrazones of substituted benzaldehydes have been prepared. The antineoplastic activity of these compounds has been assessed against murine lymphocytic leukemia P-388 and Ehrlich ascites carcinoma (EAC). The compounds investigated have not reached the criteria of good antitumor activity. However, marginal activity in P-388 system has been exhibited by one of the tested derivatives, while two others have demonstrated mild anticancer activity against EAC.

Animals↗
PubMed1982

[Ehrlich's benzaldehyde reaction (with urobilinogen) 80 years later].

The colour reaction of di-methyl-amido-benzaldehyde with metabolites in urine (especially with urobilinogen), discovered and published by Paul Ehrlich 80 years ago has lost nothing of its significance as a simple, practical, quick, qualitative test. It provides a diagnostic means in liver diseases, hemolytic processes, occlusion of the common bile duct, carcinoid and porphyrinopathies--of course, within the framework of the whole clinical picture. Despite the technical simplicity of the test, certain rules have to be adhered to. Ehrlich's aldehyde reagent has also won importance in chromatography. The modern test-strip technique permits an easy and rapid examination for urobilinogen (and bilirubin).

Benzaldehydes↗
PubMed1983

Preclinical re-evaluation of benzaldehyde as a chemotherapeutic agent.

Benzaldehyde (BA), an agent extracted from figs, is reported to have antitumor activity in vitro against a variety of experimental tumors and in vivo against refractory human neoplasms. We employed recently developed in vitro techniques to examine the effect of BA on growth of malignant human cells, and examined its effects in vivo against two human tumor xenografts established from primary specimens. BA showed dose-dependent inhibition of HL60 promyelocytic leukemia cells and normal human granulocyte/macrophage colonies. It showed no in vitro activity against either KG-1 myeloid leukemia cells or chronic lymphocytic leukemia cells grown in colony culture. BA failed to inhibit growth of either HL60 or KG-1 cells in liquid culture, and did not induce differentiation of HL60 cells. When tested against human tumor colony-forming cells from 30 patients with solid tumors, inhibition of colony growth greater than 70% was seen in six patients (20%). BA failed to inhibit the in vivo growth of either the T222 epidermoid carcinoma xenograft or the T380 ovarian carcinoma xenograft. We conclude that BA lacks significant activity against most human tumors tested in these experimental systems.

Animals↗
PubMed1981

Cytomorphological study of cultured mammalian cells treated with benzaldehyde, catechol and their derivatives with special reference to inhibition of DNA synthesis.

Cytotoxicity and cytomorphological changes induced in cultured mammalian cells by the application of benzaldehyde, pyrocatechol and their derivatives were examined. Among the compounds tested, 3,4-dihydroxybenzaldehyde (protocatechualdehyde) and 1,2-dihydroxybenzene (pyrocatechol) produced cytomorphological changes characteristic of specific inhibitors of DNA synthesis in V79 cells and EJ-1 cells. However, they did not induce such changes in HeLa cells. 2,3-Dihydroxybenzaldehyde and catecholamines did not produce such characteristic changes in V79 cells. The cytological effects of protocatechualdehyde and pyrocatechol were confirmed by a study on the incorporation of 3H-precursors of DNA, RNA and protein into 3 cell lines.

Animals↗
PubMed2000

Development of an unusually highly enantioselective hetero-Diels-Alder reaction of benzaldehyde with activated dienes catalyzed by hypercoordinating chiral aluminum complexes

The effect of Lewis acid catalysis of the hetero-Diels-Alder reaction between benzaldehyde and activated dienes (e.g. the Danishefsky's diene) has been investigated. In the present work we decided to study a series of chiral aluminum complexes as potential catalysts for the hetero-Diels-Alder reaction in order to gain a better understanding of the effect on the chiral induction of varying the steric and electronic environment of the metal ion. The results of this study prompted us to conclude that steric effects in the ligand coordination sphere and hypercoordination are strongly contributing factors to the optical yield of the reaction. Optimization of the reaction culminated in the synthesis of the hetero-Diels-Alder product in 99.4% ee and 97% yield of the isolated product. Based on the experimental results the mechanism for the hetero-Diels-Alder reaction is discussed and it is postulated that hypercoordination to the chiral aluminum Lewis acid center is of importance for the reaction.

Journal Article↗
PubMed2002

Homo- and heterochiral alkylzinc fencholates: linear or nonlinear effects in dialkylzinc additions to benzaldehyde.

Scalemic mixtures of chiral anisyl fenchols with different ortho-substituents (X) in the anisyl moieties [X = H (1), Me (2), SiMe3 (3) and tBu (4)] are employed as pre-catalysts in enantioselective additions of diethylzinc to benzaldehyde. While a remarkable asymmetric depletion is apparent for X = H and Me, a linear relationship between the enantiomeric purity of the chiral source and the product 1-phenylpropanol is observed for X = SiMe3 and tBu. X-ray single crystal analyses show that racemic methylzinc fencholates obtained from 1 (X = H) and 2 (X = Me) yield homochiral dimeric complexes, while for 3 (X = SiMe3) and 4 (X = tBu) the heterochiral dimeric alkylzinc structures are formed. The enantiopure fenchols 1-4 all yield homochiral dimeric methylzinc complexes. Computed relative energies of homo- and heterochiral fencholate dimers with X = H and Me reveal an intrinsic preference for the formation of the homochiral dimers, consistent with the observed negative NLE. In contrast, similar stabilities are computed for homo- and heterochiral complexes of ligands 3 (X = SiMe3) and 4 (X = tBu), in agreement with the absence of a nonlinear effect for bulky ortho-subsituents.

Journal Article↗
PubMed2006

Operational concept for the improved synthesis of (R)-3,3'-furoin and related hydrophobic compounds with benzaldehyde lyase.

Biphasic reaction systems for enzyme catalysis are an elegant way to overcome limited solubility and stability of reactants and facilitate continuous processes. However, many synthetically useful enzymes are not stable in biphasic systems of water and organic solvent. The entrapment in polymer beads of polyvinyl alcohol has been shown to enable the stable operation of enzymes unstable in conventional biphasic reaction systems. We report the extension of this concept to continuous operation in a fluidised bed reactor. The enzyme benzaldehyde lyase was used for the continuous synthesis of enantiopure (R)-3,3'-furoin. The results show enhanced stability with half-life times under operation conditions of more than 100 h, as well as superior enzyme utilisation in terms of productivity. Furthermore, racemisation and oxidation of the product could be successfully prevented under the non-aqueous and inert reaction conditions.

Aldehyde-Lyases↗
PubMed2007

The production of (R)-2-hydroxy-1-phenyl-propan-1-one derivatives by benzaldehyde lyase from Pseudomonas fluorescens in a continuously operated membrane reactor.

Benzaldehyde lyase (BAL; E.C. 4.1.2.38) from Pseudomonas fluorescens Biovar I catalyzes the reversible formation of benzoins from aromatic aldehydes, and, moreover, the coupling of aromatic with aliphatic aldehydes yielding derivatives of (R)-2-hydroxy-1-phenyl- propan-1-one (R)-HPPs), which are important chiral building blocks. In this paper, we report on the development of a reactor system that allows the selective production of substituted (R)-HPP-derivatives. The reaction systems yielding (R)-1-(3-chloro-phenyl)-2-hydroxy- propan-1-one, (R)-2-hydroxy-3-methoxy-1-(4-methoxy-phenyl)-propan-1-one, and (R)-2-hydroxy-3,3-dimethoxy-1-phenyl-propan-1-one were investigated. A kinetic model optimized by batch experiments was developed, for the description of both batch and continuously operated reactors. This model was used to describe the HPP production in a continuously operated enzyme membrane reactor. The reactor type used combines the advantages of high conversion and excellent selectivity with high space-time yields and total turnover numbers of up to ttn=43,000. Products were obtained in high yield on a gram scale.

Acetone↗
PubMed2004

A study of the 17O carbonyl chemical shifts in substituted benzaldehydes.

An analysis of 17O carbonyl chemical shifts of 50 substituted benzaldehydes leads to an empirical equation, delta(cal)(17O) = 564.0 + (sigma)(delta)o + (sigma)(delta)m + (sigma)(delta)p + C, for calculating 17O chemical shifts. This equation is based on a linear regression analysis using 11 substituent parameters and leads to good conformity with the expected data.

Journal Article↗
PubMed1999

Microwave Spectrum and Molecular Conformation of (E)-Benzaldehyde Oxime.

The microwave spectrum of (E)-benzaldehyde oxime, C(6)H(5)-CH&dbond;NOH and C(6)H(5)-CH&dbond;NOD, has been observed in the frequency range from 26.5 to 40.0 GHz. The spectrum of the ground vibrational state was assigned and fitted to the Watson's A-reduced Hamiltonian to obtain these rotational and centrifugal distortion constants: A = 5183.13(29) MHz, B = 895.367(3) MHz, C = 763.819(3) MHz, Delta(J) = 0.019(3) kHz, and Delta(JK) = 0.204(7) kHz for the normal species, and A = 5158.4(23) MHz, B = 869.44(2) MHz, C = 744.34(2) MHz, Delta(J) = 0.023(2) kHz, and Delta(JK) = 0.193(7) kHz for the deuterated species. The values of the DeltaI (=I(c) - I(a) - I(b)) obtained for the normal and deuterated species were -0.295(6) and -0.28(5) a.m.u. Å(2), respectively. The molecular conformation of this molecule was a planar one in which the values of the dihedral angles, CCNO and CNOH, were almost 180 degrees and 180 degrees, respectively. Copyright 1999 Academic Press.

Journal Article↗
PubMed1977

Cervical dilatation with 16,16 dimethyl PGE2 p-benzaldehyde semicarbazone ester prior to vacuum aspiration in first trimester nulliparae.

The efficacy of 16,16 dimethyl PGE2 p-benzaldehyde semicarbazone ester for cervical dilatation prior to evacuation of the uterus in 180 first trimester nulliparae has been studied. The drug was injected into the muscle of the cervix 3 hours before vacuum aspiration. In 143 patients (80%) the cervix had dilated adequately to enable evacuation of the uterus without mechanical dilatation. In the remaining 37 patients (20%) the cervix had dilated to 6 or 7 mm and additional mechanical dilatation could be performed easily in most of these patients. Side effects consisted of vomiting (11%), diarrhoea (7%), transient pyrexia and shivering (7%). There were no complications in any of the patients and no perforation of the uterus or damage to the cervix resulted during evacuation.

Abortion, Induced↗
PubMed1984

Maternal plasma estradiol and progesterone levels during therapeutic abortion induced by 16, 16 dimethyl PGE2 p-benzaldehyde semicarbazone ester.

Estradiol and progesterone levels in maternal plasma after administration of 16, 16-dimethyl-PGE2 p-benzaldehyde semicarbazone ester (16,16-PGE2) 6 hourly for abortion were studied in 27 women in the second trimester of pregnancy and in 49 patients with fetal death in utero. Basal maternal plasma levels of estradiol and progesterone measured before prostaglandin injection were significantly lower in cases of fetal death in utero than in the other subjects. After 16,16-PGE2 injection, plasma levels of estradiol and progesterone fell more rapidly and to a greater extent in cases of fetal death in utero than those with normal pregnancy at corresponding gestations; the decline of plasma estradiol levels was quicker and more marked than that of progesterone. Thus, 16,16-PGE2 appears to exert a differential effect on estradiol and progesterone biosynthesis.

16,16-Dimethylprostaglandin E2↗
PubMed1994

Cloning and sequencing of the gene encoding benzaldehyde lyase from Pseudomonas fluorescens biovar I.

The gene (bzl) encoding benzaldehyde lyase (BL) from Pseudomonas fluorescens biovar I has been cloned and characterized. The nucleotide sequence contains an open reading frame encoding a protein of 563 amino acids. The deduced BL protein shares little homology with proteins contained in the NBRF-PIR data bank. However, the higher homologies (up to about 28%) were obtained with enzymes that also utilize thiamine pyrophosphate as a cofactor.

Aldehyde-Lyases↗