Formation of mevalonic acid, sterols and bile acids from [1-14C]acetyl-CoA and [2-14C]malonyl-CoA in the liver of rabbits with experimental hypercholesterolemia

The effect of cholesterol diet on the rate of mevalonic acid biosynthesis from 1-14C acetyl-CoA, 2-14C malonyl-CoA and the incorporation of these substrates into sterols and bile acids in rabbit liver were studied. Simultaneously, the activities of 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CoA reductase) and acetyl-CoA carboxylase and the biosynthesis of fatty acids from acetyl-CoA and malonyl-CoA were measured. Hypercholesterolemia was found to be concomitant with the inhibition of acetyl-CoA carboxylase activity only in cell-free (700 g) and mitochondrial fractions and slightly decreased the incorporation of acetyl-CoA and malonyl-CoA into fatty acids in the postmitochondrial fraction. The HMG-CoA reductase activity in all subcellular fractions except for the postmicrosomal one was inhibited under these conditions. A significant decrease of acetyl-CoA incorporation and an increase in malonyl-CoA incorporation into mevalonic acid in all liver fractions except for microsomal one were observed in rabbits with hypercholesterolemia. These data provide evidence for the existence of two pathways of mevalonic acid synthesis from the above-said substrates that are differently sensitive to cholesterol. Cholesterol feeding resulted in a decreased synthesis of the total unsaponified fraction including cholesterol from acetyl-CoA, malonyl-CoA and mevalonic acid. The rate of incorporation of these substrates into lanosterol was unchanged. All the indicated substrates (acetyl-CoA, malonyl-CoA, mevalonic acid) are precursors of bile acid synthesis in rabbit liver. Cholesterol feeding and the subsequent development of hypercholesterolemia resulted in bile acid synthesis stimulation, preferentially in the formation of the cholic + deoxycholic acids from these precursors.     

Acetoacetate is a cholesterogenic precursor for myelinating rat brain and spinal cord. Incorporation of label from [3-14C]acetoacetate, [14C]glucose and 3H2O

Rat pups, 3 weeks old, were injected i.p. with combinations of 3H2O and either [3-14C]acetoacetate or [14C]glucose. 3H/14C incorporation ratios were measured in lipid fractions of homogenates and myelin prepared from whole brain and spinal cord. Spinal cord synthesized at least twice as much fatty acids and 3-fold more sterols than whole brain. Both tissues used acetoacetate preferentially for sterol synthesis, whereas label from [14C]glucose was distributed between fatty acids and sterols in the same way as 3H from 3H2O. The relative contributions of acetoacetate to sterol synthesis in whole tissue and in the purified myelin fraction were about the same, both for the cerebrum and for the spinal cord.     

Incorporation of [14C]carbon dioxide and [2-14C]mevalonic acid into terpenoids of higher plants during chloroplast development

1. The incorporation of (14)CO(2) and dl-[2-(14)C]mevalonic acid into various terpenoids in developing chloroplasts in a number of seedlings has been studied. 2. beta-Carotene and phytol (from chlorophyll) tend to be heavily labelled from (14)CO(2), whereas sterols and beta-amyrin are only slightly labelled; with dl-[2-(14)C]mevalonic acid the situation is reversed. 3. The incorporation of (14)CO(2) into terpenoids is dependent on the stage of chloroplast development, whereas that of mevalonic acid is independent of chloroplast development. 4. The uptake of (14)CO(2) into beta-carotene and phytol in mature chloroplasts is very low in monocotyledons but somewhat greater in dicotyledons. 5. The results are discussed in relation to the view that terpenoid biosynthesis in developing chloroplasts is regulated by a combination of enzyme segregation and specific membrane permeability.     

Sterols of the marine sponge Petrosia weinbergi: implications for the absolute configurations of the antiviral orthoesterols and weinbersterols

The marine sponge Petrosia weinbergi was found to contain isofucosterol and clionasterol as its major sterols. The rare cyclopropyl sterol (24S,28S)-24,28-methylenestigmast-5-en-3beta-ol, previously detected as only 0.07% of the total sterols of a pelagophytic alga Pulvinaria sp., made up 6.6% of the total sterols. These sterols are believed to be the biosynthetic precursors of the antiviral orthoesterols and weinbersterols found in the same sponge. Based on the side chains of the isolated sterols, the absolute configurations of the antiviral steroid side chains are assigned to be (24R,28S)- for orthoesterol B, (24R)- for orthoesterol C, and (24S,28S)- for weinbersterols A and B.     

The chemical synthesis and biological oxidation of 7α-hydroxy[26-14C]cholesterol, 7-dehydro[26-14C]cholesterol and 26-hydroxy[26-14C]cholesterol

1. 26-Hydroxycholesterol was obtained by reducing the methyl ester of (±)-3β-hydroxycholest-5-en-26-oic acid, which was synthesized from 25-oxonorcholesterol. 2. Methods for preparing 7α-hydroxycholesterol and 7-dehydrocholesterol were modified to allow the micro-scale preparation of these [¹⁴C]sterols from [26-¹⁴C]-cholesterol. 3. 26-Hydroxycholesterol was oxidized more readily than 7α-hydroxycholesterol, 7-dehydrocholesterol or cholesterol by mitochondrial preparations from livers of mice, rats, guinea pigs, common toads (Bufo vulgaris) and Caiman crocodylus. 4. (±)-3β-Hydroxy[26-¹⁴C]cholest-5-en-26-oic acid was oxidized very rapidly to ¹⁴CO₂ by mouse and guinea-pig mitochondria without evident discrimination between the two optical isomers. 5. An enzyme system that oxidizes 26-hydroxycholesterol to 3β-hydroxycholest-5-en-26-oic acid was identified in the soluble extract of rat-liver mitochondria. This enzyme could use NADP in place of NAD but was not identical with liver alcohol dehydrogenase (EC 1.1.1.1). 6. [26-¹⁴C]Cholesteryl 3β-sulphate was not oxidized by fortified mouse-liver preparations that oxidized [26-¹⁴C]cholesterol to ¹⁴CO₂.     

Ophirasterol, a new C31 sterol from the marine sponge Topsentia ophiraphidites

Analysis of the sterol fraction obtained from the Colombian Caribbean sponge Topsentia ophiraphidites revealed that this sponge is a rich source of C30 and C31 sterols. Among them, a new C31 sterol, named ophirasterol, was isolated, and its structure was established as (22E,24R)-24-(1-buten-2-yl)cholesta-5,22-dien-3beta-ol (1) by spectral means and comparison with synthetic C-24 epimers with known configuration. Other isolated C30 and C31 sterols were the known 24-ethyl-24-methyl-22-dehydrocholesterol (2), 24-isopropyl-22-dehydrocholesterol (3), 24-isopropylcholesterol (4), 24-ethyl-24-methylcholesterol (5), 24-isopropenyl-25-methyl-22-dehydrocholesterol (6) and 24-isopropenyl-25-methylcholesterol (7), and 24-isopropenyl-22-dehydrocholesterol (8).     

Metabolism of [1-14C]glyoxylate, [1-14C]-glycollate, [1-14C]glycine and [2-14C]-glycine by homogenates of kidney and liver tissue from hyperoxaluric and control subjects

1. The metabolism of [1-(14)C]glyoxylate to carbon dioxide, glycine, oxalate, serine, formate and glycollate was investigated in hyperoxaluric and control subjects' kidney and liver tissue in vitro. 2. Only glycine and carbon dioxide became significantly labelled with (14)C, and this was less in the hyperoxaluric patients' kidney tissue than in the control tissue. 3. Liver did not show this difference. 4. The metabolism of [1-(14)C]glycollate was also studied in the liver tissue; glyoxylate formation was demonstrated and the formation of (14)CO(2) from this substrate was likewise unimpaired in the hyperoxaluric patients' liver tissue in these experiments. 5. Glycine was not metabolized by human kidney, liver or blood cells under the conditions used. 6. These observations show that glyoxylate metabolism by the kidney is impaired in primary hyperoxaluria.     

The genome of the sponge Amphimedon queenslandica provides new perspectives into the origin of Toll-like and interleukin 1 receptor pathways

Members of the Toll-like receptor (TLR) and the interleukin 1 receptor (IL1R) superfamilies activate various signaling cascades that are evolutionarily conserved in eumetazoans. In this study, we have searched the genome and expressed sequence tags of the demosponge Amphimedon queenslandica for molecules involved in TLR and IL1R signaling. Although we did not identify a conventional TLR or ILR, the Amphimedon genome encodes two related receptors, AmqIgTIRs, which are comprised of at least three extracellular IL1R-like immunoglobulins (Ig) and an intracellular TLR-like Toll/interleukin1 receptor/resistance (TIR) domain. The remainder of the TLR/IL1R pathway is mostly conserved in Amphimedon and includes genes known to interact with TLRs and IL1Rs in bilaterians, such as Toll-interacting protein (Tollip) and myeloid differentiation factor 88 (MyD88). By comparing the sponge genome to that of nonmetazoan eukaryotes and other basal animal phyla (i.e., placozoan and cnidarian representatives) we can infer that most components of the signaling cascade, including the receptors, evolved after the divergence of metazoan, and choanoflagellate lineages. In most cases, these proteins are composed of metazoan-specific domains (e.g., Pellino) or architectures (e.g., the association of a death domain with a TIR domain in the MyD88). The dynamic expression of the two AmqIgTIRs, AmqMyD88, AmqTollip, and AmqPellino during Amphimedon embryogenesis and larval development is consistent with the TLR/IL1R pathway having a role in both development and immunity in the last common metazoan ancestor.     

Incorporation of dl-[2-14C]ornithine and dl-[5-14C]arginine in milk constituents by the isolated lactating sheep udder

1. Lactating mammary glands of sheep were perfused for several hours in the presence of dl-[2-(14)C]ornithine or dl-[5-(14)C]arginine and received adequate quantities of acetate, glucose and amino acids. 2. In the [(14)C]ornithine experiment 1.4% of the casein and 1% of the expired carbon dioxide came from added ornithine; 96% of the total radioactivity in casein was recovered in proline; 13% of the proline of casein originated from plasma ornithine. 3. In this experiment the results of chemical degradation of proline of casein as well as relative specific activities in the isolated products are consistent with the view that ornithine is metabolized, by way of glutamic gamma-semialdehyde, to proline or glutamic acid. 4. In the [(14)C]arginine experiments 3% of the casein and 1% of the expired carbon dioxide came from arginine; 84% of the arginine and 9% of the proline of casein originated from plasma arginine. 5. In these experiments the relative specific activities of arginine, ornithine and proline in plasma are in agreement with the view that arginine is metabolized by way of ornithine to proline. The conversion of arginine into ornithine is probably catalysed by arginase, so that arginase in mammary tissue may be involved in the process of milk synthesis.     

DNA adducts in rats and mice following exposure to [4-14C]-1,2-epoxy-3-butene and to [2,3-14C]-1,3-butadiene

1,3-Butadiene (BD) is a major industrial chemical and a rodent carcinogen, with mice being much more susceptible than rats. Oxidative metabolism of BD, leading to the DNA-reactive epoxides 1,2-epoxy-3-butene (BMO), 1,2-epoxy-3,4-butanediol (EBD) and 1,2:3,4-diepoxybutane (DEB), is greater in mice than rats. In the present study the DNA adduct profiles in liver and lungs of rats and mice were determined following exposure to BMO and to BD since these profiles may provide qualitative and quantitative information on the DNA-reactive metabolites in target tissues. Adducts detected in vivo were identified by comparison with the products formed from the reaction of the individual epoxides with 2'-deoxyguanosine (dG). In rats and mice exposed to [4-14C]-BMO (1-50 mg/kg, i.p.), DNA adduct profiles were similar in liver and lung with N7-(2-hydroxy-3-butenyl)guanine (G1) and N7-(1-(hydroxymethyl)-2-propenyl)guanine (G2) as major adducts and N7-2,3,4-trihydroxybutylguanine (G4) as minor adduct. In rats and mice exposed to 200 ppm [2,3-14C]-BD by nose-only inhalation for 6 h, G4 was the major adduct in liver, lung and testes while G1 and G2 were only minor adducts. Another N7-trihydroxybutylguanine adduct (G3), which could not unambiguously be identified but is either another isomer of N7-2,3,4-trihydroxybutylguanine or, more likely, N7-(1-hydroxymethyl-2,3-dihydroxypropyl)guanine, was present at low concentrations in liver and lung DNA of mice, but absent in rats. The evidence indicates that the major DNA adduct formed in liver, lung and testes following in vivo exposure to BD is G4, which is formed from EBD, and not from DEB.     

[14C]acetylcholine synthesis and [14C]carbon dioxide production from [U-14C]glucose by tissue prisms from human neocortex.

1. [14C]Acetylcholine synthesis and 14CO2 production from [U-14C]glucose has been measured in tissue prism preparations from human neocortex. 2. Electron micrographs of prisms from human and rat neocortex show that both contain intact synaptic endings with evenly-distributed vesicles and normal-appearing mitochondria, but only poorly preserved cell body structure. 3. Synthesis of [14C]acetylcholine in prisms from rat neocortex is similar to estimates for turnover in vivo. Synthesis in prisms from human neocortex is 18% of that in rat tissue and 64% of that in tissue from baboon neocortex for incubations performed in 31 mM-K+. 4. Investigations of prisms prepared from rat brains stored at 37 degrees C after death revealed that synthesis of [14C]acetylcholine in the presence of 31 mM-K+ was greatly decreased within 30 min of post-mortem incubation, whereas synthesis at 5 mM-K+ and production of 14CO2 at both K+ concentrations were only significantly affected after longer periods. Changes were similar in neocortex and striatum. Thus human autopsy material is unlikely to be suitable for use with this system. 5. Investigations using animal models suggest that [14C]acetylcholine synthesis and 14CO2 production are not affected by surgical or anaesthetic procedures. 6. Neither [14C]acetylcholine synthesis nor 14CO2 production in human prisms was significantly changed with age between 15 and 68 years. 7. Samples from patients with the dementing condition Alzheimer's disease showed a significant decrease in [14C]acetylcholine synthesis to 47% of normal samples and a significant increase of 39% in production of 14CO2.     

Tumor uptake studies of d,l-[5-14C]ornithine and d,l-2-difluoromethyl[5-14C]ornithine

The feasibility of d,l-[5-¹⁴C]ornithine ([¹⁴C]ornithine), a precursor for polyamine synthesis, and d,l-2-difluoromethyl[5-¹⁴C]ornithine ([¹⁴C]DFMO), an irreversible inhibitor of ornithine decarboxylase (ODC) were investigated for tumor localization. As an animal model, mice bearing mammary carcinoma, FM3A, were used. After i.v. injection of [¹⁴C]ornithine accumulation of radioactivity was observed in the FM3A, in which 43% of the ¹⁴C radioactivity was measured in the polyamine pool and 41% in the amino acid pool at 60 min after injection. Tumor uptake of [¹⁴C]DFMO was relatively low but constant during 60 min after injection. At 60 min after injection, 11% of the ¹⁴C was present in the acid-precipitable fraction of the FM3A, which suggests the formation of an irreversible complex of [¹⁴C]DFMO with ODC. For both compounds rapid blood clearance and high tumor-to-organ ratios were observed. Our results indicate that in connection with an enhanced polyamine synthesis in the tumors, the compounds investigated have potential as tracers for tumor detection.     

Diversity of Mycobacterium species from marine sponges and their sensitivity to antagonism by sponge-derived rifamycin-synthesizing actinobacterium in the genus Salinispora

Eleven isolates of Mycobacterium species as well as an antimycobacterial Salinispora arenicola strain were cultured from the sponge Amphimedon queenslandica. The 16S rRNA, rpoB, and hsp65 genes from these Mycobacterium isolates were sequenced, and phylogenetic analysis of a concatenated alignment showed the formation of a large clade with Mycobacterium poriferae isolated previously from another sponge species. The separation of these Mycobacterium isolates into three species-level groups was evident from sequence similarity and phylogenetic analyses. In addition, an isolate that is phylogenetically related to Mycobacterium tuberculosis was recovered from the sponge Fascaplysinopsis sp. Several different mycobacteria thus appear to co-occur in the same sponge. An actinobacterium closely related to S. arenicola, a known producer of the antimycobacterial rifamycins, was coisolated from the same A. queenslandica specimen from which mycobacteria had been isolated. This Salinispora isolate was confirmed to synthesize rifamycin and displayed inhibitory effects against representatives from two of three Mycobacterium phylotype groups. Evidence for antagonism of sponge-derived Salinispora against sponge-derived Mycobacterium strains from the same sponge specimen and the production of antimycobacterial antibiotics by this Salinispora strain suggest that the synthesis of such antibiotics may have functions in competition between sponge microbial community members.     

Incorporation of [2-14C]mevalonic acid into phytoene by isolated chloroplasts

1. Chloroplasts prepared by the non-aqueous technique will, after fragmentation by ultrasonic treatment, incorporate [2-(14)C]mevalonic acid into phytoene, the first C(40) compound formed in the biosynthetic sequence to coloured carotenoids. 2. With suspensions containing 3.5mg. of chlorophyll, the optimum amounts of cofactor required were ATP (10mumoles), magnesium chloride (20mumoles) and glutathione (20mumoles); neither NAD(+) nor NADP(+) was required. 3. Very small amounts of squalene are also formed and synthesis is stimulated by addition of NADH or NADPH. Phytoene synthesis was not affected by the presence of these cofactors and no lycopersene (the C(40) homologue of squalene) was detected. 4. The phytol side chain of chlorophyll is also labelled under these conditions. 5. Preparations of developing chloroplasts are more active than preparations of mature chloroplasts.     

Studies on bone matrix glycoproteins. Incorporation of [1-14C]glucosamine and plasma [14C]glycoprotein into rabbit cortical bone

The radioactively labelled constituents present in bone matrix were compared 12 days after injection of either [(14)C]glucosamine or plasma [(14)C]glycoprotein. Both precursors are utilized in the synthesis of organic matrix by bone tissue. Cortical bone from animals injected with [(14)C]glucosamine contains radioactivity derived from glucosamine and plasma glycoproteins and all glycoprotein fractions are labelled. Plasma [(14)C]glycoprotein labels the less acidic glycoproteins to a greater extent than the more acidic components. An antibody has been raised against the less-acidic-glycoprotein fraction of bone. The latter contains a glycoprotein of alpha-mobility that appears to be concentrated specifically in bone tissue and which is present also in plasma. This alpha-glycoprotein accounts for a large proportion of the components labelled and retained in bone matrix after [(14)C]glucosamine injection.     

Biosynthesis of thyroglobulin. Incorporation of [1-14C]galactose, [1-14C]mannose and [4,5-3H2]leucine into soluble proteins by rat thyroids in vitro

1. Rat thyroid lobes were incubated for various periods of time in Krebs–Ringer bicarbonate containing [³H]leucine and either [1-¹⁴C]galactose or [1-¹⁴C]mannose. Radioactivity in soluble proteins was determined after their separation by sucrose-gradient centrifugation. 2. The time-course of incorporation of label from [¹⁴C]-mannose into soluble thyroid proteins was parallel to that observed for [³H]leucine. There was a lag of at least 30min. before either label appeared in non-iodinated thyroglobulin (protein 17–18s). During this time both labels were detected in two fractions known to contain subunit precursors of thyroglobulin (fractions 12s and 3–8s). Radioactivity from double-labelled fractions 12s and 3–8s was transferred to protein 17–18s during subsequent incubation in an unlabelled medium. 3. In contrast, most of the [¹⁴C]galactose was immediately incorporated into protein 17–18s. 4. During the first hour of incubation, puromycin almost completely inhibited the incorporation of label from [³H]leucine and [¹⁴C]mannose into all protein fractions, but had little effect on the incorporation of [¹⁴C]galactose into protein 17–18s. 5. These results indicate that mannose is incorporated into the carbohydrate groups of protein 17–18s at an earlier stage in its formation than galactose. It is suggested that the synthesis of the carbohydrate groups of ghyroglobulin begins soon after formation of the polypeptide components, more than 30min. before these are aggregated to protein 17–18s; carbohydrate synthesis then proceeds in a stepwise manner, galactose being incorporated at about the time of aggregation of subunits to protein 17–18s. Most, if not all, the carbohydrate is added to thyroglobulin before it is iodinated.     

The biosynthesis of phosphatidylserine and phosphatidylethanolamine from L-[3-14C]serine in isolated rat hepatocytes

Incorporation of L-[3-14C]serine into phosphatidylserine (PS) and phosphatidylethanolamine (PE) has been studied in isolated rat hepatocytes. Ethanolamine inhibited the incorporation, indicating competition with serine in the base-exchange reaction. Choline, monomethylethanolamine, dimethylethanolamine and dimethyl-3-aminopropan-1-ol had no such effect. The observed rate of PS biosynthesis corresponded to 7-17 nmol/min per liver at 0.55 mM L-serine. The results indicate that only a small fraction (1/25 to 1/70) of the PS pool equilibrates with the base-exchange enzyme, and that decarboxylation to PE occurs preferentially from this pool. The rate of PS synthesis and decarboxylation can therefore not be calculated by methods which assume random, homogeneous labelling of the total PS pool. The apparent rate of PS decarboxylation increased approx. 4-fold when L-serine increased from 0.5 to 2.25 mM, suggesting that decarboxylation of PS to PE might be regulated by the concentration of L-serine or by the amount of PS present in the hepatocyte cell membranes. Lauric, palmitic, stearic, oleic and linoleic acid decreased the rate of PS synthesis. At 0.5 mM, lauric and palmitic acid were most inhibitory. At 1.0 mM, linoleic acid was the least inhibitory fatty acid. The saturated hexaenoic and saturated tetraenoic species of PS contained 51 and 29%, respectively, of the incorporated L-[3-14C]serine. The combined monoene dienoic/diene dienoic fraction had the highest rate of synthesis judged by its relative specific activity. At 0.9 mM concentration, linoleic acid doubled the relative specific activity of the combined monoene dienoic/diene dienoic fraction of PS. Incorporation of L-[3-14C]serine into molecular species of PE resembled that into PS, both in the absence and presence of linoleic acid, suggesting that the phosphatidylserine decarboxylase (EC 4.1.1.65) has a low specificity towards the fatty acid composition of PS. The results indicate that biosynthesis of PS from L-serine occurs mainly by the base-exchange with only negligible contribution from direct incorporation of phosphatidic acid or diacylglycerol. Furthermore, the deacylation-reacylation pathway seem to contribute only little to the determination of the fatty acid composition of hepatocyte PS. Active PS turnover seems to be confined to a small fraction of the PS pool.     

Assay of glutamine phosphoribosylpyrophosphate amidotransferase using [1-14C]phosphoribosylpyrophosphate

Glutamine phosphoribosylpyrophosphate amidotransferase (EC 2.4.2.14) catalyzes the transfer of the amide group of glutamine to 5-phospho-alpha-D-ribose-1-pyrophosphate. It is the first enzyme committed to the synthesis of purines by the de novo pathway. Previous assays of enzyme activity have either measured the phosphoribosylpyrophosphate-dependent disappearance of radioactive glutamine or have linked this reaction to subsequent steps in the purine pathway. A new assay for activity of the enzyme by directly measuring the synthesis of the product of the reaction. 5-beta-phosphoribosyl-1-amine, using [1-14C]phosphoribosylpyrophosphate as substrate is described. Substrate and product are separated by thin-layer chromatography and identified by autoradiography. Glutamine or ammonia may be used as substrates; the apparent Km values of the human lymphoblast enzyme are 0.46 mM for glutamine and 0.71 mM for ammonia. GMP is a considerably more potent inhibitor of the human lymphoblast enzyme than is AMP; 6-diazo-5-oxo-L-norleucine inhibits only glutamine-dependent activity and has no effect on ammonia-dependent activity.     

New polyhydroxylated sterols stylisterols A-C and a novel 5,19-cyclosterol hatomasterol from the Okinawan marine sponge Stylissa sp

New polyhydroxylated sterols, stylisterol A-C (1-3), and a novel 5,19-cyclosterol, hatomasterol (4) were isolated from the Okinawan sponge Stylissa sp. Structural determinations of these compounds were made by spectroscopic analysis and chemical conversion. Assessment of cytotoxicity toward HeLa cells was also determined.     

Two-step regio- and stereoselective syntheses of [19F]- and [18F]-2-deoxy-2-(R)-fluoro-beta-D-allose

Replacement of specific hydroxyl groups by fluorine in carbohydrates is an ongoing challenge from chemical, biological, and pharmaceutical points of view. A rapid and efficient two-step, regio- and stereoselective synthesis of 2-deoxy-2-(R)-fluoro-beta-d-allose (2-(R)-fluoro-2-deoxy-beta-d-allose; 2-FDbetaA), a fluorinated analogue of the rare sugar, d-allose, is described. TAG (3,4,6-tri-O-acetyl-1,5-anhydro-2-deoxy-d-arabino-hex-1-enitol or 3,4,6-tri-O-acetyl-d-glucal), was fluorinated in anhydrous HF with dilute F(2) in a Ne/He mixture or with CH(3)COOF at -60 degrees C. The fluorinated intermediate was hydrolyzed in 1N HCl and the hydrolysis product was purified by liquid chromatography and characterized by 1D (1)H, (13)C, and (19)F NMR spectroscopy as well as 2D NMR spectroscopy and mass spectrometry. In addition, (18)F-labeled 2-deoxy-2-(R)-fluoro-beta-d-allose (2-[(18)F]FDbetaA) was synthesized for the first time, with an overall decay-corrected radiochemical yield of 33+/-3% with respect to [(18)F]F(2), the highest radiochemical yield achieved to date for electrophilic fluorination of TAG. The rapid and high radiochemical yield synthesis of 2-[(18)F]FDbetaA has potential as a probe for the bioactivity of d-allose.