Bacterial pigments of the aryl polyene type are structurally similar to the well-known carotenoids with respect to their polyene systems. Their biosynthetic gene cluster is widespread in taxonomically distant bacteria, and four classes of such pigments have been found. Here we report the structure elucidation of the aryl polyene/dialkylresorcinol hybrid pigments of Variovorax paradoxus B4 by HPLC-UV-MS, MALDI-MS and NMR. Furthermore, we show for the first time that this pigment class protects the bacterium from reactive oxygen species, similarly to what is known for carotenoids. An analysis of the distribution of biosynthetic genes for aryl polyenes and carotenoids in bacterial genomes is presented; it shows a complementary distribution of these protective pigments in bacteria.

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The plastid genome of lettuce (Lactuca sativa L.) cv. Berkeley was site-specifically modified with the addition of three transgenes, which encoded β,β-carotenoid 3,3'-hydroxylase (CrtZ) and β,β-carotenoid 4,4'-ketolase (4,4'-oxygenase; CrtW) from a marine bacterium Brevundimonas sp. strain SD212, and isopentenyl diphosphate isomerase from a marine bacterium Paracoccus sp. strain N81106. Constructed transplastomic lettuce plants were able to grow on soil at a growth rate similar to that of non-transformed lettuce cv. Berkeley and generate flowers and seeds. The germination ratio of the lettuce transformants (T0) (98.8%) was higher than that of non-transformed lettuce (93.1 %). The transplastomic lettuce (T1) leaves produced the astaxanthin fatty acid (myristate or palmitate) diester (49.2% of total carotenoids), astaxanthin monoester (18.2%), and the free forms of astaxanthin (10.0%) and the other ketocarotenoids (17.5%), which indicated that artificial ketocarotenoids corresponded to 94.9% of total carotenoids (230 μg/g fresh weight). Native carotenoids were there lactucaxanthin (3.8%) and lutein (1.3 %) only. This is the first report to structurally identify the astaxanthin esters biosynthesized in transgenic or transplastomic plants producing astaxanthin. The singlet oxygen-quenching activity of the total carotenoids extracted from the transplastomic leaves was similar to that of astaxanthin (mostly esterified) from the green algae Haematococcus pluvialis.

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Our prognostic prediction model for estimating 14-day survival for patients with terminal cancer on the PCU ward included five clinical predictors that are readily available in the clinical setting and showed a relatively high accuracy. External validation is needed to confirm the model's generalizability.

We have clearly identified the structural motifs of 19-nor-1alpha,25(OH)(2)D(3) analogs responsible for differentiation and apoptosis in HL-60 cells. These findings will provide useful information not only for development of therapeutic agents for treatment of leukemia and other cancers, but also for structure-function studies of 1alpha,25(OH)(2)D(3).

We performed the chemical mutagenesis of Halobacillus halophilus (the producer of a C 30 carotenoid, methyl glucosyl-3,4-dehydro-apo-8¢-lycopenoate) to isolate novel carotenoids that are biosynthetic intermediates of methyl glucosyl-3,4-dehydroapo-8¢-lycopenoate. As a result, we isolated two novel C 30 carotenoids, hydroxy-3,4-dehydro-apo-8¢-lycopene and methyl hydroxy-3,4-dehydro-apo-8¢-lycopenoate, which were biosynthesized through a novel 8¢-apo C 30 pathway. These carotenoids showed antioxidative activity in the 1 O 2 suppression model.

Transition state control in BINOL-Ti-catalyzed asymmetric carbonyl-ene cyclization by tuning the 6-Br-BINOL ligand completes the synthesis of the A ring of the 2-methyl-19-nor-22-oxa D 3 analogue (2), which shows the significant activity in differentiation of HL-60 cell.Basic research on the synthesis of analogues of the biologically active form of vitamin D 3 , 1a,25-dihydroxyvitamin D 3 [1a,25(OH) 2 D 3 ], has brought about the development of an important new field in medicinal chemistry. 2 A number of analogues have been synthesized and used to clarify the mode of action of vitamin D hormones and find new therapeutically useful compounds. These analogues are useful not only for calcium metabolism disorder and bone diseases, but also for differentiation of myelocytic leukemias and the treatment of psoriasis. 3 10-Oxo-19-nor-25(OH) 2 D 3 has been reported to exhibit a selective activity for differentiation of myelocytic leukemias. 4 19-Nor1a,25(OH) 2 D 3 also shows a selective activity profile, i.e., high potency in differentiation of malignant cells, but low calcitropic liability. 5 22-Oxa-1a,25(OH) 2 D 3 (OCT) shows a significant activity in the inhibition of cancer cell growth. 6 We have thus reported the hybridization analogue, 7 19-nor-22-oxa-1a,25(OH) 2 D 3 (1) on the basis of asymmetric carbonyl-ene cyclization 8b catalyzed by a binaphthol-derived titanium (BINOL-Ti) complex. 9 Recent papers 10 prompt us to report the synthesis of 2-methyl-19-nor-22-oxa vitamin D 3 analogue (2) 1,11 by tuning the chiral ligands for the ene cyclization 12 (Scheme 1) and the significant activity in differentiation of myelocytic leukemia, HL-60 cell.The preparation of the 2-methyl ene-cyclization substrate ((R,R)-3) is worth mentioning (Scheme 2). The allylic alcohol (7) was obtained through highly regioselective propiolate-ene reaction using triisopropylsilyl ethers (5) 13 (regioisomer ratio = 94:6) 14 with methyl propiolate (6) using EtAlCl 2 as the promoter. The ene substrate 3 was prepared in 96% ee via catalytic enantioselective epoxidation of allylic alcohol 15 (7) with (S,S)-diethyl tartrate (DET), O OBn OMPM OBn OMPM HO HO O OH OH HO O OH OH (R,R)-3 (R)-6-Br-BINOL-Ti