6-Hydrazinonicotinic hydrazide hydrate - ≥97%

Cat. No.: H469995

GRADE & PURITY ≥97%

Synonyms

6-Hydrazino-3-pyridinecarboxylic acid hydrazide hydrate

Storage

Room temperature

Specifications

Sinonimi

6-Hydrazino-3-pyridinecarboxylic acid hydrazide hydrate

Specifiche e purezza

≥97%

Condizioni di conservazione di stoccaggio

Room temperature

Purezza

≥97%

Application Protocols

No Aladdin-specific, validated application protocols are provided for this SKU. The following generalized, literature-based workflow illustrates typical use in bioconjugation; adjust to your system and consult primary sources.

Example: Conjugation to oxidized glycoproteins

• Oxidation (glycan activation):
  • Dissolve target glycoprotein (e.g., 1–10 mg/mL) in 100 mM sodium acetate, pH 5.5. Add freshly prepared NaIO4 to 1–5 mM. Incubate on ice, dark, 15–30 min. Quench with 10–20 mM ethylene glycol, 10 min.
• Coupling:
  • Desalt/rapidly buffer-exchange into fresh acetate buffer. Add 6-hydrazinonicotinic hydrazide hydrate (5–50 mM stock in water/DMSO) to 5–20 molar equivalents over estimated aldehyde sites. Incubate 1–4 h at room temperature or 4 °C overnight.
• Optional stabilization:
  • Add picoline borane (5–20 mM) or NaBH3CN under pH 5.5–6.5 to reduce hydrazones to stable secondary amines; incubate 1–2 h.
• Cleanup:
  • Remove excess small molecules by desalting column, dialysis, or spin ultrafiltration (e.g., 10–30 kDa MWCO as appropriate). Analyze by SDS-PAGE, UV/Vis, and MS if available.

Small-molecule carbonyl coupling

• Mix carbonyl partner (1.0 equiv) with the reagent (1.2–3.0 equiv) in 100 mM acetate, pH 5.2 (0–20% DMF if needed). Stir 1–6 h at RT; monitor by LC–MS. Optionally reduce in situ for stable products.

Note: These are illustrative conditions only and are not product-specific recommendations. Validate on small scale before preparative use.

Biological Roles

This compound is a synthetic chemical tool and does not have a known natural biological role. The following points describe its relevance in biochemical workflows (general literature context; no clinical claims):

• Bioconjugation handle:

  • Hydrazide and hydrazino groups form reversible covalent bonds (hydrazones) with aldehydes/ketones on biomolecules (e.g., oxidized glycans), enabling preparation of protein, peptide, and polysaccharide conjugates for analytical and research applications.

• Tagging and immobilization:

  • Facilitates attachment of biomolecules to aldehyde-functionalized surfaces (chips, beads) or introduces additional functional handles via carbonyl linkers for downstream modifications.

• Coordination platform in research radiochemistry:

  • Hydrazinonicotinic scaffolds can serve as bifunctional anchors that first attach to biomolecules and subsequently participate in coordination chemistry with certain transition metals in research tracer development (strictly non-clinical laboratory use).

• Enzyme interactions:

  • No specific enzymatic substrate or inhibitor roles are established for this reagent. Hydrazine-containing species can, in general, react with carbonyl cofactors, but such interactions are context dependent and not the intended use.

• Stability in biological media:

  • Hydrazones formed at mildly acidic pH can hydrolyze; stabilization by reduction (to secondary amines) is often used when greater robustness is required for biological assays.

Note: Any use with biological materials should be validated for compatibility, activity retention, and absence of undesired crosslinking. Always maintain appropriate biosafety practices.

Buffer Applications

While not a classical buffering agent, this reagent is commonly used in buffered systems for carbonyl–hydrazide conjugation. The buffer primarily controls reaction rate and selectivity, not pH stabilization by the reagent itself.

• Typical buffer systems (literature guidance):

  • Sodium acetate (50–200 mM), pH 4.5–5.5: widely used for hydrazone formation with aldehydes; balances protonation (activation of carbonyl) and hydrazide nucleophilicity.
  • Citrate buffer (50–100 mM), pH 5–6: alternative to acetate with similar performance; useful in metal-sensitive contexts.
  • Phosphate buffer (50–100 mM), pH 6–7.4: slower hydrazone formation; may be used when biomolecule stability demands near-neutral pH; consider nucleophilic catalysis (e.g., aniline derivatives) to accelerate.

• Additives and conditions:

  • Aniline or anthranilate catalysts (10–100 mM) can significantly increase rates at neutral pH; evaluate EHS profile and downstream removal.
  • Sodium chloride (up to isotonic levels) can improve protein stability; avoid high salt with metal-coordination steps.

• Practical recipes (examples; adjust to your system):

  • 100 mM sodium acetate, pH 5.2; dissolve the reagent to 5–50 mM immediately before use.
  • For biomolecule conjugation: oxidize glycans with freshly prepared NaIO4 in cold acetate buffer, quench excess oxidant (e.g., with ethylene glycol), then perform hydrazide coupling.

• Compatibility:

  • Avoid buffers containing reactive carbonyls (e.g., formaldehyde) or primary amines in high excess that can compete or interfere with hydrazone formation.

Green Alternatives

Sustainable practice focuses on solvent choice, atom economy, and minimizing hazardous reagents when working with hydrazide-based conjugations.

• Greener solvent choices (literature guidance):

  • Prefer water or aqueous acetate/citrate buffers for hydrazone formation; these conditions typically provide high selectivity and reduce VOC emissions.
  • If a cosolvent is needed, small percentages of ethanol or propylene carbonate may substitute for DMF/DMSO where substrate solubility permits.

• Catalyst considerations:

  • Aniline catalysis can accelerate hydrazone formation but introduces toxicity concerns. Alternatives such as anthranilic acid or p-aminobenzoic acid have been reported as less hazardous nucleophilic catalysts, though with varied efficiency.

• Reductive stabilization:

  • If stabilization of hydrazones is required, consider milder, safer reductants (e.g., picoline borane) instead of sodium cyanoborohydride, while evaluating efficacy and safety for your system.

• Waste minimization:

  • Conduct conjugations at higher concentrations in water to reduce solvent waste; use stoichiometric balance to limit excess reagent. Implement aqueous workups and dialysis/ultrafiltration instead of large-volume organic extractions for biomolecule conjugates.

• Comparison snapshot (general):

  • Aqueous buffer vs DMF-rich media: aqueous systems reduce toxicity and allow simpler disposal; DMF may improve solubility of hydrophobic partners but increases EHS burden.
  • Ethanol cosolvent vs acetonitrile: ethanol offers better EHS metrics and renewability, though acetonitrile can give faster kinetics in some systems.

• Energy efficiency:

  • Reactions usually proceed at ambient temperature; avoid unnecessary heating or cryogenic steps to decrease energy use.

Pharmaceutical Uses

No excipient or pharmacopeial status is specified for this item; it is supplied strictly as a Research Use Only reagent.

• Not for clinical use: This product is not intended for human or veterinary administration, diagnostic procedures, or GMP manufacturing.

• Relevance in pharmaceutical research (general):

  • Bioconjugation: Used to prepare conjugates of biomolecules with analytical tags or linkers via hydrazone formation to aldehydes/ketones (e.g., oxidized glycans). Such conjugates can be characterized in discovery settings (e.g., binding studies, analytical tracking).
  • Radiochemistry tool: Hydrazinonicotinic scaffolds are used as bifunctional anchors in the preparation of research radiotracers; any such use must remain in non-clinical R&D.

• Formulation considerations (research context):

  • If incorporated into analytical reagents, choose aqueous buffers at pH 4.5–6 to support shelf-stable formulations; store aliquots to minimize repeated freeze–thaw when cold storage is used.
  • Avoid excipients containing reactive carbonyls (e.g., reducing sugars) which can consume hydrazide functionality.

• Documentation:

  • No USP/EP/JP monograph is implied. For any regulated research workflow, rely on the Aladdin CoA for lot-specific quality attributes and perform incoming qualification as needed (identity by NMR/LC–MS, assay by titration/HPLC).

Physical Properties

Item-specific physical specifications (for this SKU):

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular Weight: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular Formula: Not specified for this item; refer to CoA/Spec Sheet.
• Boiling point, melting point, density, UV cutoff, water or peroxide content: Not specified for this item; refer to CoA/Spec Sheet.

General/literature expectations for this compound class (informational, not specifications):

• Physical state: typically isolates as a crystalline hydrate; hydrazide/hydrazino pyridines are generally high-melting solids due to hydrogen bonding and lattice water.
• Solubility: good solubility in polar media (water, aqueous buffers, DMSO) and limited solubility in nonpolar organic solvents; hydrazide salts (if formed) show enhanced water solubility.
• Acid–base behavior: hydrazino nitrogens are basic/nucleophilic and can be protonated under acidic conditions; pyridine ring nitrogen also basic (pKaH of pyridine ~5.2, literature), facilitating buffer compatibility at mildly acidic to neutral pH.
• UV/Vis: aromatic pyridine systems absorb in the UV; specific extinction coefficients are method- and solvent-dependent (consult CoA/SDS or measure empirically for analytical use).

Practical notes:

• Dissolution is typically fastest in water or aqueous acetate/citrate buffers (pH 4–6) for hydrazone-forming reactions.
• Hygroscopicity may be observed for hydrates; weigh rapidly and keep container closed to minimize water uptake or loss.
• For precise numeric values relevant to your lot (e.g., hydration level, assay), consult the Aladdin CoA.

Quality and Grades

• Grade/Purity (Product Data): Not specified for this item; refer to CoA/Spec Sheet.
• Research Use Note: For research use only.

Interpretation and guidance:

• Research use only (RUO) indicates the product is intended for laboratory research and development. It is not validated for diagnostic or therapeutic use, nor for use in humans or animals for clinical purposes.
• In the absence of a stated grade (e.g., AR, Biotech, HPLC), users should consult the CoA for assay, water of hydration, residual solvents, and any specific impurity profile relevant to their application (e.g., trace metals if intended for coordination chemistry studies).
• Hydrate form: The hydration state can influence assay by weight and solubility. If your workflow requires molarity-based dosing, determine the exact hydration level from the CoA or by thermogravimetry/Karl Fischer as needed.
• UV background: If using for conjugation with UV-based analytics (HPLC/UV), confirm the UV absorbance profile of your lot to set appropriate detection wavelengths and baselines.
• Bioconjugation suitability: For carbohydrate/aldehyde coupling, low levels of carbonyl contaminants and low bioburden are desirable; review CoA and, if necessary, perform pre-use purification (e.g., recrystallization) to meet stringent analytical criteria.
• Documentation: Aladdin provides lot-specific CoA upon shipment; contact us if your regulatory environment requires supplemental documentation (e.g., statement of origin, residual solvent statement).

Reaction and Applications

Key chemistries enabled by 6-hydrazinonicotinic hydrazide hydrate stem from its dual hydrazino/hydrazide functionalities and the coordinating pyridine ring.

• Hydrazone/imine formation (literature):

  • Rapid, chemoselective coupling to aldehydes and ketones forms hydrazones; widely used for bioconjugation to oxidized glycans on glycoproteins, polysaccharides, and lipopolysaccharides.
  • Typical conditions: pH 4.5–6 (acetate/citrate buffer), ambient temperature to 37 °C, with optional aniline catalysis to accelerate rates.

• Oxidative glycan activation:

  • Periodate oxidation of vicinal diols on carbohydrates generates aldehydes that couple with the hydrazide; quench excess oxidant before coupling.

• Ligand/chelation roles in research radiochemistry (general):

  • Hydrazinonicotinyl motifs are used as bifunctional anchors for technetium and rhenium coordination chemistry with appropriate co-ligands and reducing agents; the hydrazinonicotinic core facilitates attachment to biomolecules via hydrazone linkages prior to complexation. Use strictly in research settings.

• Further derivatization:

  • The carboxylic hydrazide can be acylated to give acyl hydrazides or converted to acyl azides (via nitrosation/activation) for subsequent Curtius-type rearrangements (exercise caution and follow safety protocols).
  • The ring hydrazino group can be selectively protected (e.g., Boc, Cbz) to control reactivity in stepwise syntheses.

• Analytical tagging:

  • Reaction with aldehyde-bearing dyes or carbonyl-modified linkers allows construction of probes; hydrazones can be stabilized by sodium cyanoborohydride or pyridine borane (reductive amination-like stabilization).

• Practical considerations:

  • Control pH carefully; excessive acidity fully protonates hydrazines, reducing nucleophilicity; excessive basicity can promote hydrolysis.
  • Use freshly prepared solutions to minimize background oxidation of hydrazino nitrogens.

Reaction Conditions

General literature guidance for common transformations with 6-hydrazinonicotinic hydrazide hydrate (verify and optimize for your system):

• Hydrazone formation with aldehydes/ketones:

  • Solvent: water or 50–200 mM acetate/citrate buffer; optional 0–20% DMSO/DMF for solubility.
  • pH: 4.5–6 (faster at mildly acidic pH); at pH 7–7.4 use nucleophilic catalysts (e.g., aniline derivatives, 10–100 mM) to accelerate.
  • Temperature: 20–37 °C.
  • Time: 0.5–24 h depending on substrate and pH.
  • Stoichiometry: 1.1–5.0 equiv of hydrazide relative to limiting carbonyl.
  • Workup: desalting, dialysis/SEC for biomolecules; for small molecules, concentration and purification by chromatography.

• Reductive stabilization of hydrazones:

  • Reagents: sodium cyanoborohydride or picoline borane (safer alternative) in aqueous buffer/alcohol mixtures; maintain pH ~5–7 to balance activity and safety.
  • Temperature/time: ambient, 1–4 h typically.

• Periodate oxidation of carbohydrates (for biomolecule preparation, handle with care):

  • Reagents: NaIO4 (1–10 mM) in cold, dark conditions; quench with ethylene glycol or sodium sulfite before coupling.

• Metal coordination research (hydrazinonicotinyl scaffolds):

  • Conditions vary by metal; for technetium/rhenium studies, reactions often use reducing agents (e.g., stannous salts) at pH ~5–7 with appropriate co-ligands; strictly research-only protocols.

• Protection/deprotection:

  • Protect one hydrazine with Boc or Cbz in dry DMF/DCM with base; deprotect under standard acidolysis/hydrogenolysis conditions, monitoring to avoid N–N cleavage.

Always perform small-scale trials to establish kinetics and selectivity with your substrates. Consult primary literature for exact procedures.

Safety and Handling

Authoritative safety information is provided in the product SDS. The following is general guidance for hydrazine-containing aromatic hydrazides and does not replace the SDS.

• Product Data hazards for this SKU:

  • Signal Word: Not specified for this item; refer to SDS.
  • H-Statements: Not specified for this item; refer to SDS.
  • GHS Classification/Pictograms: Not specified for this item; refer to SDS.

• General hazards (literature/analogy for hydrazides/hydrazines):

  • Toxicity/irritation: hydrazine derivatives can be harmful if swallowed or inhaled and may cause skin/eye irritation or sensitization; avoid aerosol generation.
  • Reactive functionality: hydrazino groups are nucleophilic and can react with aldehydes/ketones; avoid unintended exposure to reactive carbonyls (e.g., formaldehyde) and strong oxidizers.
  • Thermal stability: high-melting solids; decomposition possible at elevated temperature with nitrogen-containing fumes.

• PPE and handling:

  • Wear lab coat, safety glasses or face shield, and appropriate chemically resistant gloves (e.g., nitrile). Use a certified fume hood when weighing and preparing solutions.
  • Avoid contact with acids/oxidizers unless intended by protocol; hydrazide solutions are best prepared fresh to minimize degradation.

• First aid (overview; follow SDS/medical guidance):

  • Skin/eye contact: rinse with copious water for at least 15 minutes; remove contaminated clothing; seek medical attention.
  • Inhalation: move to fresh air; monitor respiration; obtain medical attention.
  • Ingestion: rinse mouth; do not induce vomiting unless instructed; seek immediate medical advice.

• Storage incompatibilities: keep away from strong oxidizers, aldehyde vapors, acid chlorides/anhydrides (uncontrolled acylation), and strong acids/bases that may promote decomposition.

Solvent Selection

This compound is a polar, multifunctional aromatic hydrazide/hydrazine, typically handled as a solid or in aqueous/polar solutions.

• Polarity/miscibility (general, literature):

  • Readily soluble in water and common polar organic solvents such as DMSO and DMF; limited solubility in alcohols may require warming; poorly soluble in nonpolar solvents (hexanes, toluene).
  • For bioconjugation (hydrazone formation), aqueous acetate or citrate buffers at pH ~4.5–6 are commonly used; addition of small amounts of DMF or DMSO (≤10–20%) can aid dissolution without impeding reaction rates.

• When to choose aqueous vs organic:

  • Aqueous buffers: preferred for coupling to biomolecules (oxidized glycans on glycoproteins, polysaccharides) to maintain biological integrity.
  • Mixed aqueous/organic: useful for small-molecule carbonyl partners with limited water solubility.

• Dielectric and donor properties (qualitative):

  • Multiple basic nitrogens confer high hydrogen-bond donor/acceptor capacity, favoring high-dielectric media for rapid reaction and stability.

• Practical tips:

  • Prepare fresh solutions to minimize background oxidation or self-condensation.
  • Filter sterilize (0.22 μm) if using with sensitive biomolecules; avoid alcohol sterilization which can react with activated carbonyls.
  • Avoid strong acids during dissolution to prevent excessive protonation that can reduce nucleophilicity; mildly acidic buffers balance solubility and reactivity.

• Alternative solvents for challenging substrates:

  • NMP or sulfolane (anhydrous) for high-temperature small-molecule derivatizations; ensure compatibility with substrates and removal under reduced pressure.

Storage and Reconstitution

• Storage Conditions (Product Data): Room temperature.
• Shipped In: Not specified for this item; refer to CoA/Spec Sheet.

Good practice (general guidance for hydrazide/hydrazine reagents; do not override Product Data):

• Keep container tightly closed in a dry place. Although supplied as a hydrate, minimize unnecessary exposure to ambient humidity to preserve consistent hydration level and assay by weight.
• Protect from strong light and reactive vapors (e.g., aldehydes, acid chlorides, oxidants) during storage.
• If long-term storage is anticipated, consider subdividing into small, single-use portions to avoid repeated opening. Some users store at 2–8 °C for extended periods; ensure containers are well sealed to prevent moisture exchange and condensation on warming.

Reconstitution/solution preparation:

• Use clean, oxygen-free water or buffer (e.g., degassed acetate pH 5–6) to prepare fresh stock solutions immediately before use. Typical working concentrations: 1–100 mM depending on application.
• If required, co-solvents like DMSO or DMF (≤20%) facilitate dissolution of hydrophobic partners. Filter sterilize (0.22 μm) for sensitive bioconjugations.
• Avoid prolonged storage of aqueous solutions; if necessary, aliquot and freeze at −20 °C to −80 °C, minimizing freeze–thaw cycles. Inspect for precipitation or discoloration before use; discard if degraded.

Labeling and documentation:

• Record preparation date, solvent, concentration, and any additives on the vial. For exact stability and any special requirements for this lot, consult the Aladdin CoA and SDS.

Structure and Identity

Brief overview: 6-Hydrazinonicotinic hydrazide hydrate is a bifunctional, nitrogen-rich pyridine derivative featuring both a ring-bound hydrazino substituent and a carboxylic hydrazide, supplied as a hydrate. It is widely used in conjugation and labeling chemistries where hydrazide/hydrazino groups form reversible hydrazones with carbonyl partners.

• Item-specific identifiers (from Product Data):

  • CAS: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular Formula: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular Weight: Not specified for this item; refer to CoA/Spec Sheet.
  • SMILES: Not specified for this item; refer to CoA/Spec Sheet.
  • InChIKey: Not specified for this item; refer to CoA/Spec Sheet.

• Structural features (general, literature-based description):

  • Core ring system: pyridine (nicotinic) ring with the ring nitrogen at position 1.
  • Substitution pattern: a carboxyl-derived hydrazide (–CONHNH2) at the 3-position (nicotinoyl hydrazide), and a hydrazino substituent (–NHNH2) at the 6-position on the ring.
  • Hydrate: includes bound water of crystallization (stoichiometry can vary; verify on CoA for this lot).
  • Functional groups: two nucleophilic hydrazine-type moieties capable of forming imines/hydrazones with aldehydes/ketones; amide (hydrazide) capable of further derivatization (acylation/activation).

• 2D description in words:

  • A six-membered aromatic ring containing one ring nitrogen (pyridine). At the meta position relative to the ring nitrogen (nicotinic-3-position) is an amide carbonyl linked to –NH–NH2 (hydrazide). At the 6-position of the ring is –NH–NH2 (hydrazino). The compound is present as a hydrate, typically isolating as a crystalline solid with lattice water.

• Stereochemistry: none (achiral, no stereocenters).

Synthetic Utility

The molecule combines three key reactive elements—pyridine nitrogen, ring hydrazino group (–NH–NH2), and carboxylic hydrazide (–CONH–NH2)—which provide versatile entry points in synthesis.

• As a bifunctional linker:

  • Hydrazide couples to aldehydes/ketones forming hydrazones; subsequent reduction furnishes stable secondary amines, effectively converting carbonyl partners into amine-linked conjugates on a pyridyl scaffold.

• Orthogonal derivatization strategies:

  • Selective protection of one hydrazine (e.g., Boc on terminal –NH2) allows stepwise construction of asymmetrically substituted derivatives.
  • Acylation of the terminal hydrazide nitrogen yields acyl hydrazides/hydrazones that can be transformed further (e.g., Wolff–Kishner-like or Shapiro-type pathways are not applicable directly but analogous N–N functional modifications are possible with due control).

• Activation to acyl azides (caution):

  • The hydrazide carbonyl can be converted to an acyl azide via nitrosation and subsequent rearrangement chemistry (Curtius-type downstream) to access amines, ureas, or carbamates on a pyridyl backbone; rigorous safety protocols are mandatory for azide chemistry.

• Coordination/ligand elaboration:

  • The pyridine nitrogen and adjacent hydrazino functionality support construction of chelating frameworks for transition-metal complexes in methodology studies.

• Retrosynthetic value:

  • Provides a pre-installed hydrazide handle on a heteroaromatic core, enabling rapid access to libraries of conjugates by simple carbonyl coupling under mild, aqueous conditions—valuable in late-stage functionalization of carbonyl-bearing leads or biomolecules.

• Analytics:

  • Conjugates can be tracked by UV (pyridine absorbance) and MS (characteristic N-rich isotopic patterns). Employ orthogonal methods (NMR, HPLC) to confirm hydrazone vs reduced-linkage states.

Target Specificity

Not applicable. This product is a small-molecule reagent, not a biological targeting agent. No antigen, epitope, species reactivity, clone, or isotype information is associated with this item. For intended uses, refer to the Reaction & Applications and Application Protocols sections.