Coordination Patterns of the Diphosphate in IDP Coordination Complexes: Crystal Structure and Chirality.

The knowledge of accurate geometrical parameters from X-ray diffraction studies in the solid state of metal nucleotide is very important for understanding the relationship between structures and properties, including biochemical processes and even enzyme-metal-substrate interactions. The research is also very necessary to precisely and controllably design the functional materials. Here, seven types of coordination polymers of inosine 5'-diphosphate nucleotide (IDP) with transition metals, {[Zn(HIDP)(azpy)(H2O)2]·4H2O}n (1), {[Cd2(IDP)2(bpda)2]·[Cd(H2O)6]·11H2O}n (2), {[Cd3(IDP)2(4,4'-bipy)2(H2O)3]·6H2O}n (3), {[Cd2(IDP)2(bpe)2(H2O)2]·(H2bpe)·26H2O}n (4), {[Cu3(IDP)2(azpy)2(H2O)5]·5H2O}n (5), {[Cu3(IDP)2(bpe)2(H2O)5]·9H2O}n (6), and {[Co(HIDP)(azpy)(H2O)2]·7H2O}n (7) [4,4'-bipy = 4,4'-bipyridine, azpy = 4,4'-azopyridine, bpe = 1,2-bis(4-pyridyl)ethene, and bpda = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene], were designed, synthesized, and firmly characterized using single-crystal X-ray diffraction. The coordination patterns of the diphosphate group of IDP in these complexes were studied by crystallographic analysis, namely, open, close, and open-close hybrid types. We have investigated the diverse coordination patterns of the diphosphate group and its spatial relationship relative to the pentose ring on the basis of two conformational parameters, the pseudorotation phase angle and the degree of puckering. Crystallographic studies clearly reveal the correlation between the backbone torsion angle (ω' and φ) of the sugar-diphosphate and the conformational preference of the pentose ring, i.e., the signs of the backbone torsion angles ω' and φ are both plus (+) or minus (-), the conformation of the pentose ring is envelope form (E), while when one of the two signs is plus (+) and the other is minus (-), the pentose ring is in the twist form (T). This is the first time elucidation of the coordination pattern of diphosphate relative to the conformation of the pentose ring in nucleotide metal complexes, which are different from the other inorganic or organic diphosphate compounds. The chirality of these coordination polymers was examined by combining solid-state circular dichroism spectroscopy measurements with the explanation of their crystal structures. The results presented in this paper are very important for understanding their nucleotide coordination chemistry, their supramolecular chemistry, and even their biochemistry.

Exploring enantioselective recognition of dTMP-Co-bpe coordination polymer for natural amino acids using molecular simulations and circular dichroism.

The 1D homochiral coordination polymer (CP-1) {[Co(dTMP)(bpe)2(H2O)3]·9H2O}n was constructed by using 2'-deoxy thymidine 5'-monophosphate disodium salt (dTMP·2Na), and auxiliary ligand bpe (1,2-bis(4-pyridyl)ethene) and characterized by single-crystal XRD, PXRD, IR, UV-visible, CD and TGA analyses. Molecular simulations revealed the selective chiral behaviour of CP-1 towards phenylalanine and histidine, as indicated by their higher binding free energies compared to other amino acids. Theoretical parameters were also compared with experimental UV-visible verdicts. Notably, the D-enantiomers of phenylalanine and histidine demonstrated strong bonding abilities and optimal configurations for probing and distinguishing them from their L-counterparts. These findings led to propositions suggesting that the dissimilarities between these D and L amino acid forms and their binding orientations with CP-1 may contribute to alterations in the CD signal. CP-1 exhibited a robust inherent circular dichroism (CD) signal in aqueous solutions, modulated by the presence of specific amino acids, namely D/L phenylalanine and D/L histidine. Leveraging the measurement of CD signal intensity, a sensor capable of detecting unmodified amino acids has been developed. Unlike previously reported approaches that relied on complex chemical reactions between initially CD-silent molecules and probed amino acids, this new method offers a more straightforward means of amplifying the CD signal. Consequently, this change facilitates a more accurate differentiation between the enantiomers of these specific amino acids compared to others.

Improving the performance status in advanced non-small cell lung cancer patients with chemotherapy (ImPACt trial): a phase 2 study.

PURPOSE: This phase II trial is designed to test whether the performance status (PS) of metastatic non-small cell lung cancer (mNSCLC) patients (pts) can improve with chemotherapy if their poor PS (Eastern Cooperative Oncology Group (ECOG) PS of ≥ 2) is due to disease burden rather than comorbidities. METHODS: Age18-65 years, Charlson's comorbidity index < 9, serum albumin ≥ 3.5 g/dl, adequate bone marrow and organ function, & ECOG PS ≥ 2 as judged by the worst score of three independent physicians were administered 3 doses of weekly paclitaxel at 60 mg/m2/dose. The primary endpoint was an improvement in ECOG PS by 1 point at 4 weeks; others: toxicity (CTCAE v 5.0), quality of life (QoL) assessment at baseline and 4 weeks by EORTC QLQ-C30 and EORTC QLQ-LC13. Optimal Simon's 2-stage design was used. RESULTS:  Forty-six patients were included with a median age of 56 years (interquartile range, IQR 54-59), 12 (26%) had comorbid conditions, and 87% with ECOG PS 3/4. PS improved in 11 pts at 4 weeks and in 7 beyond this time point. Grade 3/4 toxicities are seen in 20% (most common: anemia and diarrhea). At a median follow-up of 4.8 m (95% CI 3.27-14.9), the median progression-free survival and overall survival were 3.3 months (95% CI 2.36-5.6) and 6.8 months (95% CI 2.47-8.8), respectively. QoL improved for global QoL, role functioning, pain, dyspnea, insomnia, pain in the chest, pain in other parts, and worsened for alopecia and sore mouth. CONCLUSIONS:  Abbreviated chemotherapy is a useful, well-tolerated strategy in carefully selected poor PS mNSCLC patients that can improve PS and QoL. CLINICAL TRIAL: Clinical trial information: CTRI/2020/01/022617.

Controllable synthesis of two adenosine 5'-monophosphate nucleotide coordination polymers via pH regulation: crystal structure and chirality.

Two types of Cu(ii)-AMP-4,4'-bipy coordination polymers, {[Cu(AMP)(4,4'-bipy)(H2O)3]·5H2O}n (1) and {[Cu2(HAMP)2(4,4'-bipy)2(H2O)4]·2NO3·11H2O}n (2) (Na2AMP = adenosine 5'-monophosphate disodium salt), were synthesised through pH control. X-ray single-crystal diffraction analysis revealed that 1 and 2 are one-dimensional (1D) coordinating coordination polymers. The nucleotide in 1 was not protonated whereas that in 2 was protonated. With the protonated NO3- in 2 entering the crystal lattice, it plays a role in balancing the charge. The chirality was studied using solid-state circular dichroism (CD) spectroscopy based on the analysis of crystal structures.