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Key research themes
1. How do intramolecular and intermolecular hydrogen bonding interactions influence the structural conformation and tautomerism in aromatic Schiff bases and related compounds?
This research theme investigates the role of hydrogen bonds—both within molecules (intramolecular) and between molecules (intermolecular)—in dictating molecular conformations, tautomeric forms, and crystal packing in Schiff bases and related aromatic compounds. Understanding these interactions is crucial for rationalizing stability, reactivity, and potential biological activities, as hydrogen bonding governs molecular arrangement, tautomeric shifts, and supramolecular architectures.
Key finding: This study revealed that the title Schiff base crystallizes predominantly in the phenol-imine tautomeric form, stabilized by a strong intramolecular O-H...N hydrogen bond forming an S(6) ring motif. Additionally, the... Read more
Key finding: The compound forms intramolecular O-H...O hydrogen bonds generating S(6) motifs that stabilize molecular conformation and weak intramolecular C-H...N contacts forming S(7) ring motifs. In the crystal, molecules form inversion... Read more
Key finding: The crystal structure analysis revealed that protonation induces a planar pyrimidinium cation, where N-H...O hydrogen bonds with trifluoroacetate anions generate centrosymmetric 2+2 aggregates featuring R2 2(8) and R4 2(8)... Read more
2. What structural features and intermolecular interactions govern the packing motifs and stability in heterocyclic aromatic compounds with pharmacological or catalytic relevance?
This theme focuses on the crystallographic characterization of heterocyclic aromatic compounds, many of which possess biological or catalytic properties, analyzing key intermolecular forces such as halogen bonding, π–π stacking, C-H...π interactions, and hydrogen bonding that dictate molecular packing and stability. Insights into spatial arrangement and interaction motifs facilitate the understanding of how molecular architecture impacts functional properties.
Key finding: X-ray crystallography identified that the red isomer of an indolothiopyranthione crystallizes with solvent inclusion and forms centrosymmetric pairs via π–π stacking interactions with centroid distances of 3.56 Å arranged in... Read more
Key finding: This structural study of a tetramethylated biphenylazepine revealed the preparation of a chiral ligand scaffold exhibiting significant steric hindrance designed to enhance central-to-axial chirality induction. Though... Read more
Key finding: Beyond hydrogen bonding, the compound exhibits multiple intermolecular interactions including F···H/H···F and C···H/H···C contacts quantified by Hirshfeld surface analysis, contributing 20.6% and 15.4%, respectively,... Read more
3. How can synthetic strategies coupled with structural elucidation via crystallography advance the design of biologically active heterocyclic scaffolds and related organic compounds?
This theme centers on the integrated approach of chemical synthesis and single-crystal X-ray diffraction to develop novel heterocyclic entities with biological relevance. Through detailed structural characterization, synthetic modifications influencing molecular conformation, tautomerism, and substituent orientation are related to potential pharmacological profiles and chemical reactivity, guiding rational design principles for medicinal chemistry and catalysis.
Key finding: The compound was synthesized via reflux and crystallized to reveal a molecular framework wherein the oxadiazolethione ring is nearly orthogonal to the substituted pyrazole moiety. The crystal structure shows rotational... Read more
Key finding: Through a multistep synthesis involving acylation and cyclization, an unexpected 1-methyl-3-enamino tetramic derivative was isolated. Crystallographic and NMR analyses confirmed the enamino tautomeric forms, and antibacterial... Read more
Key finding: This work reports the formation of a novel chromeno-pyridine derivative via an ohmic-heating-assisted multicomponent Hantzsch reaction. Structural elucidation confirmed the unexpected compound, highlighting the influence of... Read more