Milbemectin a4

• CAS: 51596-11-3
• Catalog Number: ACM51596113
• Category: Main Products
• Molecular Weight: 542.7
• Molecular Formula: C₃₂H₄₆O₇
• Synonyms: milbemycinb-1;MILBEMECTIN A4;milbemectine a4;milbemycin A4;(25R)-25-Ethyl-5β-hydroxy-5-demethoxy-28-O,6β-cyclomilbemycin B;(6R,25R)-5-O-Demethyl-28-deoxy-6,28-epoxy-25-ethylmilbemycin B;Antibiotic B-41A4;Milbemycin α3
• IUPAC Name: milbemycin A4
• Boiling Point: 732.9ºC at 760mmHg
• Flash Point: 233.3ºC
• Density: 1.2g/cm³
• Appearance: white solod
• Exact Mass: 542.32400
• Packing Group: III

Case Study

Engineered Biosynthesis of Milbemectin in Streptomyces avermitilis

Kim, Myoun-Su, et al. Microbial cell factories 16 (2017): 1-16.

Milbemycins are valuable 16-membered macrolides known for their strong acaricidal, insecticidal, and anthelmintic properties and low toxicity. The objective was to engineer the high-yielding avermectin producer Streptomyces avermitilis SA-01 to efficiently produce milbemycins, specifically targeting milbemectin (a mixture of milbemycins A3 and A4), addressing increasing resistance to avermectins.
Engineering Strategy & Strain Development
· The polyketide synthase (PKS) pathway in S. avermitilis SA-01 was modified to redirect biosynthesis towards milbemycins:
· Key components of the avermectin PKS (AveA1 and AveA3, or specifically module 7 of AveA3) were replaced with their milbemycin PKS counterparts (MilA1 and MilA3, or module 7 of MilA3).
· This engineered strain produced milbemycins A3, A4, and D in small amounts, with milbemycins B2, B3, and G (C5-O-methylated congeners) as major products, achieving a total titer of approximately 292 mg/L.
· To enhance production of the non-methylated milbemectin components (A3/A4), the C5-O-methyltransferase gene aveD was subsequently inactivated.
Production Results
The engineered strain with inactivated aveD demonstrated significantly improved production of the target compounds. Milbemectin (milbemycins A3/A4) production reached approximately 225 mg/L in flask culture. Scalability was confirmed, with milbemectin (milbemycins A3/A4) production increasing to 377 mg/L in a 5L fermenter.

Nematicidal Efficacy of Milbemectin Against Root-Knot Nematodes

Talavera-Rubia, et al. Plants 9.7 (2020): 839.

Root-knot nematodes cause significant agricultural damage. This case study evaluates the nematicidal performance of milbemectin - a defined mixture of 30% milbemycin A3 and 70% milbemycin A4 - and its commercial formulation across key biological targets: egg hatching, juvenile motility, and infectivity.
Key Findings
· In Vitro Efficacy: Exposure of nematode egg masses to 30 μg/mL milbemectin for 72 hours reduced egg hatching by 52%, with extended exposure (240 hours) at lower concentrations (15 and 7 μg/mL) achieving 35% and 24% inhibition, respectively, while milbemectin also caused persistent, concentration-dependent juvenile immobilization (41-87%) even after rinsing, with calculated lethal concentrations of LC50 = 7.4 μg/mL and LC90 = 29.9 μg/mL.
· In Planta Efficacy: Pre-plant application of milbemycin formulation to infested soils in pot experiments reduced nematode root infectivity by 98-99% compared to untreated controls, and under natural field infestations, it reduced soil nematode population densities by 50-60%, demonstrating significant practical control.

Custom Q&A

What is the molecular formula of Milbemectin a4?

The molecular formula of Milbemectin a4 is C32H46O7.

What are the synonyms of Milbemectin a4?

The synonyms of Milbemectin a4 include Milbemycin A4, EMAMECTIN A4, ANTIBIOTIC B 41A4, and MILBEMYCIN .ALPHA.3, among others.

What is the CAS number of Milbemectin a4?

The CAS number of Milbemectin a4 is 51596-11-3.

What is the IUPAC name of Milbemectin a4?

The IUPAC name of Milbemectin a4 is (1R,4S,5'S,6R,6'R,8R,10E,13R,14E,16E,20R,21R,24S)-6'-ethyl-21,24-dihydroxy-5',11,13,22-tetramethylspiro[3,7,19-trioxatetracyclo[15.6.1.14,8.020,24]pentacosa-10,14,16,22-tetraene-6,2'-oxane]-2-one.

What is the InChIKey of Milbemectin a4?

The InChIKey of Milbemectin a4 is VOZIAWLUULBIPN-LRBNAKOISA-N.

What is the molecular weight of Milbemectin a4?

The molecular weight of Milbemectin a4 is 542.7g/mol.

How many hydrogen bond donor counts are there in Milbemectin a4?

There are 2 hydrogen bond donor counts in Milbemectin a4.

How many hydrogen bond acceptor counts are there in Milbemectin a4?

There are 7 hydrogen bond acceptor counts in Milbemectin a4.

How many rotatable bond counts are there in Milbemectin a4?

There is 1 rotatable bond count in Milbemectin a4.

What is the exact mass of Milbemectin a4?

The exact mass of Milbemectin a4 is 542.32435380g/mol.